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, 3 insertions, 3 deletions

diff --git a/libs/hwui/LayerRenderer.cpp b/libs/hwui/LayerRenderer.cpp
index 2a4e72be0e31..65f8c7c8b67c 100644
--- a/libs/hwui/LayerRenderer.cpp
+++ b/libs/hwui/LayerRenderer.cpp
@@ -37,7 +37,7 @@ LayerRenderer::LayerRenderer(Layer* layer): mLayer(layer) {
 LayerRenderer::~LayerRenderer() {
 }
 
-void LayerRenderer::prepareDirty(float left, float top, float right, float bottom, bool opaque) {
+int LayerRenderer::prepareDirty(float left, float top, float right, float bottom, bool opaque) {
     LAYER_RENDERER_LOGD("Rendering into layer, fbo = %d", mLayer->getFbo());
 
     glBindFramebuffer(GL_FRAMEBUFFER, mLayer->getFbo());
@@ -57,9 +57,9 @@ void LayerRenderer::prepareDirty(float left, float top, float right, float botto
         mLayer->region.subtractSelf(r);
     }
 
-    OpenGLRenderer::prepareDirty(dirty.left, dirty.top, dirty.right, dirty.bottom, opaque);
+    return OpenGLRenderer::prepareDirty(dirty.left, dirty.top, dirty.right, dirty.bottom, opaque);
 #else
-    OpenGLRenderer::prepareDirty(0.0f, 0.0f, width, height, opaque);
+    return OpenGLRenderer::prepareDirty(0.0f, 0.0f, width, height, opaque);
 #endif
 }