Implement native key pre-dispatching to IMEs.

This significantly re-works the native key dispatching code to
allow events to be pre-dispatched to the current IME before
being processed by native code.  It introduces one new public
API, which must be called after retrieving an event if the app
wishes for it to be pre-dispatched.

Currently the native code will only do pre-dispatching of
system keys, to avoid significant overhead for gaming input.
This should be improved to be smarted, filtering for only
keys that the IME is interested in.  Unfortunately IMEs don't
currently provide this information. :p

Change-Id: Ic1c7aeec8b348164957f2cd88119eb5bd85c2a9f

1 files changed, 5 insertions, 1 deletions

diff --git a/native/android/input.cpp b/native/android/input.cpp
index 4e1b6dcb042d..59bf71178f7c 100644
--- a/native/android/input.cpp
+++ b/native/android/input.cpp
@@ -248,7 +248,7 @@ void AInputQueue_detachLooper(AInputQueue* queue) {
     queue->detachLooper();
 }
 
-int AInputQueue_hasEvents(AInputQueue* queue) {
+int32_t AInputQueue_hasEvents(AInputQueue* queue) {
     return queue->hasEvents();
 }
 
@@ -256,6 +256,10 @@ int32_t AInputQueue_getEvent(AInputQueue* queue, AInputEvent** outEvent) {
     return queue->getEvent(outEvent);
 }
 
+int32_t AInputQueue_preDispatchEvent(AInputQueue* queue, AInputEvent* event) {
+    return queue->preDispatchEvent(event) ? 1 : 0;
+}
+
 void AInputQueue_finishEvent(AInputQueue* queue, AInputEvent* event, int handled) {
     queue->finishEvent(event, handled != 0);
 }