This PR makes the Linux key handling code a little more lenient when it comes to the order in which it receives responses to key events from the framework. I had assumed that there wasn't a case where responses could get out of order, but it seems that it is possible, given that you can mash on the keyboard and eventually get one out of order.
This changes the code so that instead of just looking at the first entry in the pending event deque, it searches the deque starting at the beginning to find the event, and remove it.
This changes the text handling so that keyboard events are sent to the framework first for handling, and then passed to the text input plugin, so that the framework has a chance to handle keys before they get given to the text field.
This is complicated by the async nature of the interaction with the framework, since GTK wants a synchronous response. So, in this change, I always tell GTK that the event was handled, and if it wasn't, then I re-dispatch the event once we know one way or the other.
Switches the Linux embedding from the standard C API to the new proctable version, to allow for unit testing of the embedding layer separately from the embedder APIs implementation.
We currently use a mix of C standard includes (e.g. limits.h) and their
C++ variants (e.g. climits). This migrates to a consistent style for all
cases where the C++ variants are acceptable, but leaves the C
equivalents in place where they are required, such as in the embedder
API and other headers that may be used from C.
Make a single-param ctor explicit in order to prevent surprising
implicit conversions.
Add a check for zero message-size and don't malloc/memcpy the incoming
message in those cases.
Add braces where they were missing.
Simplify FlDartProject by removing the path arguments - we'll assume that it's
in the standard bundle layout and add new methods later if we need to support
other cases.
