Track canvas clearing for swap buffers logic.

A previous fix made it necessary for a frame to render something to GL
in order to cause a call to eglSwapBuffers(). Besides the calls being
tracked as part of issuing a DisplayList, there is also a potential call
to clear the canvas (via glClear()) on non-opaque surfaces. This call is also
good to track, since a surface that gets cleared without any other drawing operations
is worth flipping to the screen (to erase old contents on that surface).

This fix tracks the status of the pre-draw operations to find out whether
glClear() was called and then sets the drawing status appropriately.

Issue #6606422 QuickContact dismissal is janky again (Tracking)

Change-Id: I5fcaccfdc9293dd46b83f2fc279730a5d2740ebf

1 files changed, 2 insertions, 1 deletions

diff --git a/libs/hwui/DisplayListRenderer.cpp b/libs/hwui/DisplayListRenderer.cpp
index 88d2209..d376e3a 100644
--- a/libs/hwui/DisplayListRenderer.cpp
+++ b/libs/hwui/DisplayListRenderer.cpp
@@ -1368,13 +1368,14 @@ void DisplayListRenderer::setViewport(int width, int height) {
     mHeight = height;
 }
 
-void DisplayListRenderer::prepareDirty(float left, float top,
+int DisplayListRenderer::prepareDirty(float left, float top,
         float right, float bottom, bool opaque) {
     mSnapshot = new Snapshot(mFirstSnapshot,
             SkCanvas::kMatrix_SaveFlag | SkCanvas::kClip_SaveFlag);
     mSaveCount = 1;
     mSnapshot->setClip(0.0f, 0.0f, mWidth, mHeight);
     mRestoreSaveCount = -1;
+    return DrawGlInfo::kStatusDone; // No invalidate needed at record-time
 }
 
 void DisplayListRenderer::finish() {