Currently, TabChild discards eKeyDown and eKeyPress events which are marked as
"repeated" and were dispatched after the latest eKeyDown event comes into the
process. However, keyboard layout utils may generate native key events
as "repeated" even if each native key is important to input proper text.
So, TabChild shouldn't decide if coming keyboard event is skippable only with
mIsRepeat. For solving this issue, this patch adds
mMaybeSkippableInRemoteProcess to WidgetKeyboardEvent and makes
TabChild::SkipRepeatedKeyEvent() check
WidgetKeyboardEvent::CanSkipInRemoteProcess() instead.
On Windows, there are two ways to generate keyboard input messages. One is
using SendMessage() or PostMessage(). The other is SendInput() API. In both
ways, utils can make their input as repeated key messages.
The former case must be safe for this issue since such utils need to set 31st
bit of lParam to 1 explicitly.
On the other hand, in the latter case, the utils probably need to append
KEYEVENTF_KEYUP into KEYBDINPUT::dwFlags. Otherwise, only first call is
treated as non-repeated event.
So, when given message does not came from physical key operation, NativeKey
should set WidgetKeyboardEvent::mMaybeSkippableInRemoteProcess to false
even if WidgetKeyboardEvent::mIsRepeat is true.
MozReview-Commit-ID: 3rinrOjx8Tf
--HG--
extra : rebase_source : 26b6d869260176fc7ef535323b83001bb4b725c2