Add NativeViewGLSurfaceEGL::CommitOverlayPlanes support for Android

ui/gl/gl_surface_egl.cc

Index: ui/gl/gl_surface_egl.cc
diff --git a/ui/gl/gl_surface_egl.cc b/ui/gl/gl_surface_egl.cc
index 8352ff6b1f501b4a7091092720272ccd4ce7476a..21b9f159619e0cd268b19cf6382452ef6e0a09d5 100644
--- a/ui/gl/gl_surface_egl.cc
+++ b/ui/gl/gl_surface_egl.cc
@@ -683,6 +683,9 @@ gfx::SwapResult NativeViewGLSurfaceEGL::SwapBuffers() {
     return gfx::SwapResult::SWAP_FAILED;
   }
 
+  if (SupportsCommitOverlayPlanes() && !CommitAndClearPendingOverlays())

[piman, 2015/12/01 01:06:45]

SupportsCommitOverlayPlanes() seems orthogonal to
CommitAndClearPendingOverlays(), I think we should just always
CommitAndClearPendingOverlays() (keeping in mind that the overlay list is likely
empty). If anything just not do it if the list is empty.

It might make sense to move this before the eglSwapBuffers, in case there's an
interaction between it and the set of enabled overlays.

[watk, 2015/12/01 01:55:55]

That makes a lot of sense. Done.

+    return gfx::SwapResult::SWAP_FAILED;
+
   return gfx::SwapResult::SWAP_ACK;
 }
 
@@ -752,9 +755,26 @@ gfx::SwapResult NativeViewGLSurfaceEGL::PostSubBuffer(int x,
              << GetLastEGLErrorString();
     return gfx::SwapResult::SWAP_FAILED;
   }
+  if (SupportsCommitOverlayPlanes() && !CommitAndClearPendingOverlays())

[piman, 2015/12/01 01:06:45]

(same here)

[watk, 2015/12/01 01:55:55]

Done.

+    return gfx::SwapResult::SWAP_FAILED;
   return gfx::SwapResult::SWAP_ACK;
 }
 
+bool NativeViewGLSurfaceEGL::SupportsCommitOverlayPlanes() {
+#if defined(OS_ANDROID)
+  return true;
+#else
+  return false;
+#endif
+}
+
+gfx::SwapResult NativeViewGLSurfaceEGL::CommitOverlayPlanes() {
+  DCHECK(SupportsCommitOverlayPlanes());
+  return CommitAndClearPendingOverlays()
+             ? gfx::SwapResult::SWAP_ACK
+             : gfx::SwapResult::SWAP_FAILED;
+}
+
 VSyncProvider* NativeViewGLSurfaceEGL::GetVSyncProvider() {
   return vsync_provider_.get();
 }
@@ -764,15 +784,13 @@ bool NativeViewGLSurfaceEGL::ScheduleOverlayPlane(int z_order,
                                                   gl::GLImage* image,
                                                   const Rect& bounds_rect,
                                                   const RectF& crop_rect) {
-#if defined(OS_ANDROID)
-  // Overlay planes are used on Android for fullscreen video. The image is
-  // expected to update the plane as soon as possible to display the video frame
-  // chosen for this vsync interval.
-  return image->ScheduleOverlayPlane(window_, z_order, transform, bounds_rect,
-                                     crop_rect);
-#else
+#if !defined(OS_ANDROID)
   NOTIMPLEMENTED();
   return false;
+#else
+  pending_overlays_.push_back(
+      GLSurfaceOverlay(z_order, transform, image, bounds_rect, crop_rect));
+  return true;
 #endif
 }
 
@@ -788,6 +806,17 @@ NativeViewGLSurfaceEGL::~NativeViewGLSurfaceEGL() {
 #endif
 }
 
+bool NativeViewGLSurfaceEGL::CommitAndClearPendingOverlays() {
+  bool success = true;
+  for (const auto& overlay : pending_overlays_) {
+    // It's expected that GLImage::ScheduleOverlayPlane will overlay contents on
+    // the screen now.
+    success &= overlay.ScheduleOverlayPlane(window_);
+  }
+  pending_overlays_.clear();
+  return success;
+}
+
 PbufferGLSurfaceEGL::PbufferGLSurfaceEGL(const gfx::Size& size)
     : size_(size),
       surface_(NULL) {