[PPAPI] Add browser tests for compositor API

ppapi/proxy/compositor_layer_resource.cc

Index: ppapi/proxy/compositor_layer_resource.cc
diff --git a/ppapi/proxy/compositor_layer_resource.cc b/ppapi/proxy/compositor_layer_resource.cc
index a33f7c17f2ac7ff631f9ce49342e4fe555edc630..17bc7b2fe42287ee34a70608cad23be4e38d319d 100644
--- a/ppapi/proxy/compositor_layer_resource.cc
+++ b/ppapi/proxy/compositor_layer_resource.cc
@@ -32,11 +32,17 @@ void OnTextureReleased(
     const ScopedPPResource& context,
     uint32_t texture,
     const scoped_refptr<TrackedCallback>& release_callback,
+    int32_t result,
     uint32_t sync_point,
     bool is_lost) {
   if (!TrackedCallback::IsPending(release_callback))
     return;
 
+  if (result != PP_OK) {
+    release_callback->Run(result);
+    return;
+  }
+
   do {
     if (!sync_point)
       break;
@@ -59,11 +65,12 @@ void OnImageReleased(
     const ScopedPPResource& layer,
     const ScopedPPResource& image,
     const scoped_refptr<TrackedCallback>& release_callback,
+    int32_t result,
     uint32_t sync_point,
     bool is_lost) {
   if (!TrackedCallback::IsPending(release_callback))
     return;
-  release_callback->Run(PP_OK);
+  release_callback->Run(result);
 }
 
 }  // namespace
@@ -105,7 +112,6 @@ int32_t CompositorLayerResource::SetColor(float red,
   if (!size)
     return PP_ERROR_BADARGUMENT;
 
-
   data_.color->red = clamp(red);
   data_.color->green = clamp(green);
   data_.color->blue = clamp(blue);
@@ -207,6 +213,11 @@ int32_t CompositorLayerResource::SetImage(
   data_.image->source_rect.point = PP_MakeFloatPoint(0.0f, 0.0f);
   data_.image->source_rect.size = source_size_;
 
+  // If the PP_Resource of this layer is released by the plugin, the
+  // release_callback will be aborted immediately, but the texture or image
+  // in this layer may still being used by chromium compositor. So we have to
+  // use ScopedPPResource to keep this resource alive until the texture or image
+  // is released by the chromium compositor.
   release_callback_ = base::Bind(
       &OnImageReleased,
       ScopedPPResource(pp_resource()), // Keep layer alive.
@@ -333,7 +344,7 @@ bool CompositorLayerResource::SetType(LayerType type) {
 int32_t CompositorLayerResource::CheckForSetTextureAndImage(
     LayerType type,
     const scoped_refptr<TrackedCallback>& release_callback) {
- if (!compositor_)
+  if (!compositor_)
     return PP_ERROR_BADRESOURCE;
 
   if (compositor_->IsInProgress())