This re-lands #20496 and #21780 after fixing the semantics-enabling code that was causing the post-submit web_smoke_test to fail.
Below is the description from the original PR:
This is a PR for converting the dart:ui code in the engine to use a multi-window API. The goal here is to convert from the window singleton to an API that has the concept of multiple windows. Also, I'm matching up the new PlatformDispatcher class to talk directly to the PlatformConfiguration class in the engine. I'm not attempting to actually enable creating multiple windows here, just migrate to an API that has a concept of multiple windows. The multi-window API in this PR currently only ever creates one window.
The design doc for this change is here.
The major changes in this PR:
Move the platfom-specific attributes out of Window, and into the new PlatformDispatcher class that holds all of the platform state, so that the platform code need only update the configuration on this class.
Create FlutterView, FlutterWindow, and SingletonFlutterWindow classes to separate out the concepts of a view (of which there may be multiple in a window), a window (of which there may be multiple on a screen, and they host views), and a window where there is only ever expected to be one (this hosts the entire API of the former Window class, and will eventually be the type of the window singleton).
Next step after this PR lands:
Remove the Window class entirely (it is replaced by SingletonFlutterWindow). Some minor changes in the Framework are needed to switch to using SingletonFlutterWindow directly first.
The Window class still exists in this PR, but will be removed as soon as the framework is converted to point to the SingletonFlutterWindow class instead. They share the same API, just have different names (Window is currently a subclass of SingletonFlutterWindow). The intention is that the Window name will be freed up to use as a widget class name in the framework for managing windows. The singleton called window will remain, and keep the same API it has now.
Embedders that have access to the Dart native API (only Fuchsia now) may perform
library setup in the isolate create callback. The engine used to depend on the
fact the root isolate entrypoint is invoked in the next iteration of message
loop (via the `_startIsolate` trampoline in `isolate_patch.dart`) to ensure that
library setup occur before the main entrypoint was invoked. However, due to
differences in the way in which message loops are setup in Fuchsia, this
entrypoint was run before the callback could be executed. Dart code on Fuchsia
also has the ability to access the underlying event loops directly. This patch
moves the invocation of the create callback to before user dart code has a
chance to run. This difference in behavior on Fuchsia became an issue when the
isolate initialization was reworked in https://github.com/flutter/engine/pull/21820
for null-safety.
Another issue was discovered in that the callback was being invoked twice, I
fixed that too and added a test.
Fixes https://github.com/flutter/flutter/issues/68732
Snapshots compiled with sound null-safety enabled require changes to the way in
which isolates are launched. Specifically, the `Dart_IsolateFlags::null_safety`
field needs to be known upfront. The value of this field can only be determined
once the kernel snapshot is available. This poses a problem in the engine
because the engine used to launch the isolate at shell initialization and only
need the kernel mappings later at isolate launch (when transitioning the root
isolate to the `DartIsolate::Phase::Running` phase). This patch delays launch of
the isolate on the UI task runner till a kernel mapping is available. The side
effects of this delay (callers no longer having access to the non-running
isolate handle) have been addressed in this patch. The DartIsolate API has also
been amended to hide the method that could return a non-running isolate to the
caller. Instead, it has been replaced with a method that requires a valid
isolate configuration that returns a running root isolate. The isolate will be
launched by asking the isolate configuration for its null-safety
characteristics.
A side effect of enabling null-safety is that Dart APIs that work with legacy
types will now terminate the process if used with an isolate that has sound
null-safety enabled. These APIs may no longer be used in the engine. This
primarily affects the Dart Convertors in Tonic that convert certain C++ objects
into the Dart counterparts. All known Dart Converters have been updated to
convert C++ objects to non-nullable Dart types inferred using type traits of the
corresponding C++ object. The few spots in the engine that used the old Dart
APIs directly have been manually updated. To ensure that no usage of the legacy
APIs remain in the engine (as these would cause runtime process terminations),
the legacy APIs were prefixed with the `DART_LEGACY_API` macro and the macro
defined to `[[deprecated]]` in all engine translation units. While the engine
now primarily works with non-nullable Dart types, callers can still use
`Dart_TypeToNonNullableType` to acquire nullable types for use directly or with
Tonic. One use case that is not addressed with the Tonic Dart Convertors is the
creation of non-nullable lists of nullable types. This hasn’t come up so far in
the engine.
A minor related change is reworking tonic to define a single library target.
This allows the various tonic subsystems to depend on one another. Primarily,
this is used to make the Dart convertors use the logging utilities. This now
allows errors to be more descriptive as the presence of error handles is caught
(and logged) earlier.
Fixes https://github.com/flutter/flutter/issues/59879
This removes most of the remaining FLUTTER_NOLINT comments and opts
these files back into linter enforcement.
I've filed https://github.com/flutter/flutter/issues/68273 to require
that all FLUTTER_NOLINT comments be followed by a GitHub issue URL
describing the problem to be fixed.
* Revert "Fix documentation build for window changes. (#21780)"
This reverts commit 931a04683d6eb49fc92059b2384ac5b1618d5422.
* Revert "Migration to PlatformDispatcher and multi-window (#20496)"
This reverts commit 85b0031f73544e448354047dc6a236c0b0808252.
This is a PR for converting the dart:ui code in the engine to use a multi-window API. The goal here is to convert from the window singleton to an API that has the concept of multiple windows. Also, I'm matching up the new PlatformDispatcher class to talk directly to the PlatformConfiguration class in the engine. I'm not attempting to actually enable creating multiple windows here, just migrate to an API that has a concept of multiple windows. The multi-window API in this PR currently only ever creates one window.
The design doc for this change is here.
The major changes in this PR:
Move the platfom-specific attributes out of Window, and into the new PlatformDispatcher class that holds all of the platform state, so that the platform code need only update the configuration on this class.
Create FlutterView, FlutterWindow, and SingletonFlutterWindow classes to separate out the concepts of a view (of which there may be multiple in a window), a window (of which there may be multiple on a screen, and they host views), and a window where there is only ever expected to be one (this hosts the entire API of the former Window class, and will eventually be the type of the window singleton).
Next step after this PR lands:
Remove the Window class entirely (it is replaced by SingletonFlutterWindow). Some minor changes in the Framework are needed to switch to using SingletonFlutterWindow directly first.
The Window class still exists in this PR, but will be removed as soon as the framework is converted to point to the SingletonFlutterWindow class instead. They share the same API, just have different names (Window is currently a subclass of SingletonFlutterWindow). The intention is that the Window name will be freed up to use as a widget class name in the framework for managing windows. The singleton called window will remain, and keep the same API it has now.
Skia is removing the deprecated legacy display setting globals and
associated kLegacyFontHost_InitType. This change replaces all such uses
with default surface properties with no special flags and an unknown
pixel geometry. Flutter never set the associated globals, leaving them
with their initial default values, which were no special flags and
horizontal RGB pixel geometry. The values used here are different but
this change should make no difference as Flutter never mentions
SkFont::kSubpixelAntiAlias to take advantage of the pixel geometry.
Embedders can now notify shell during startup about the various displays and their corresponding settings.
Adds a notion of Display update type which can later include chages to displays during runtime such as addition / removal / reconfiguration of displays.
We also remove the responsibility of providing the refresh rate from `vsync_waiter` to `DisplayManager`.
Rewires existing platform implementations of the said API to use `Shell::OnDisplayUpdate` to notify the display manager of the startup configuration.
DisplayManager is also thread-safe to account for rasterizer and UI thread accesses.
Cleans up header order/grouping for consistency: associated header, C/C++ system/standard library headers, library headers, platform-specific #includes.
Adds <cstring> where strlen, memcpy are being used: there are a bunch of places we use them transitively.
Applies linter-required cleanups. Disables linter on one file due to included RapidJson header. See https://github.com/flutter/flutter/issues/65676
This patch does not cover flutter/shell/platform/darwin. There's a separate, slightly more intensive cleanup for those in progress.
Add copyright headers in a few files where they were missing.
Trim trailing blank comment line where present, for consistency with
other engine code.
Use the standard libtxt copyright header in one file where it differed
(extra (C) and comma compared to other files in libtxt).
This also amends tools/const_finder/test/const_finder_test.dart to look
for a const an additional four lines down to account for the copyright
header added to the test fixture.
The data race: gl_surface_fbo_frame_infos_ in the test context to was appended
to on the raster task runner but read on the platform task runner. This is now
sidestepped by using a callback and pushing that responsibility to the test.
Setting the callback is guarded behind a mutex.
The race condition: The assertions were previously run when the UI thread was
done generating the frames. However, the assertions were run on the results
collected on the raster thread in response the frame requests from UI thread.
Just run the assertions on the raster thread directly.
Fixes https://github.com/flutter/flutter/issues/64344
This is part of a larger effort to expose the difference between GrDirectContext,
which runs on the GPU thread and can directly perform operations like uploading
textures, and GrRecordingContext, which can only queue up work to be delivered
to the GrDirectContext later.
Tweak the primary flutter build rule so that fuchsia is more similar to
other platforms in how tests and the shell are built.
Only embedder_unittests and GLFW tests are disabled on Fuchsia now.
TEST: Ran unittests on host/fuchsia; workstation on fuchsia
BUG: fxb/53847, fxb/54056
This change makes it so that we track all the motion events encountered by `FlutterView` and all of its subviews in the `MotionEventTracker` class, indexed by a unique `MotionEventId`. This identifier is then passed to the Flutter framework as seen in https://github.com/flutter/flutter/pull/60930. Once the gestures take part in gesture disambiguation and are sent back to the engine, we look-up the original motion event using the `MotionEventId` and dispatch it to the platform.
Bug: https://github.com/flutter/flutter/issues/58837
The embedder.h API layer is an implementation detail of the desktop
embeddings, not part of the public API surface, so should not be part of
the public symbol list for those libraries.
