This allows const GlobalObjectKey(0) to be concisely formatted as
[GlobalObjectKey int#0000] in both Dart 2 and Dart 1 modes.
Without this change it would be formatted as
[GlobalObjectKey<State<StatefulWidget>> int#0000] because in Dart 2
types are instantiated to bounds.
In addition to retaining general readability this also fixes few
tests that rely on this short string representation (see
test/widgets/global_keys_duplicated_test.dart).
In some cases, the element tree is not clean but we are required to dump the tree anyway.
To avoid crashing in those cases, we return an explicit null node.
* Introduce a Directionality inherited widget which sets the ambient LTR vs RTL mode (defaulting to null, which means you cannot use directionality-influenced values).
* Make it possible to configure Padding (including Container.padding and Container.margin) using a directionality-agnostic EdgeInsets variant.
* Provide textDirection and verticalDirection controls on Row and Column to make them RTL-aware.
* Introduce a variant of FractionalOffset based on the EdgeInsets variant. Not yet actually used.
* Fix all the tests that depended on Row defaulting to LTR.
* Revert "Revert "Change all ocurrences of '$runtimeType#$hashCode' to use the idAndType method. (#10871)" (#10880)"
This reverts commit ceb814aa647ecd310794a72a7a5c28820ec57a25.
* Change all instances of '$runtimeType#$hashCode' to use the describeIdentity method.
The describeIdentity method generates a shorter description with a consistent length
consisting of the runtime type and the a 5 hex character long truncated
version of the hash code.
* Add more tests of toStringDeep.
These tests will help ensure toStringDeep behavior is not regressed
by refactoring toStringDeep to support structured data.
Rename State.config to State.widget
Rename State.didUpdateConfig to State.didUpdateWidget
Renamed all State subclasses' local variables named config to something else
