gpu: Make sure to add composer flag to buffers used with SurfaceControl

The API docs mention that this flag should be added to buffers destined
for HardwareComposer. It was inadvertantly removed in:
https://chromium-review.googlesource.com/c/chromium/src/+/2036374

R=liberato@chromium.org,vikassoni@chromium.org

Bug: 1021007
Change-Id: If8e3b8f8fad7219829d8866fead24b844baef9df
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2036486
Auto-Submit: Khushal <khushalsagar@chromium.org>
Reviewed-by: Frank Liberato <liberato@chromium.org>
Commit-Queue: Khushal <khushalsagar@chromium.org>
Cr-Commit-Position: refs/heads/master@{#738389}

gpu/command_buffer/service/image_reader_gl_owner.cc

@@ -110,6 +110,8 @@ ImageReaderGLOwner::ImageReaderGLOwner(
   uint64_t usage = mode == Mode::kAImageReaderSecureSurfaceControl
                        ? AHARDWAREBUFFER_USAGE_PROTECTED_CONTENT
                        : AHARDWAREBUFFER_USAGE_GPU_SAMPLED_IMAGE;
+  if (IsSurfaceControl(mode))
+    usage |= AHARDWAREBUFFER_USAGE_COMPOSER_OVERLAY;
 
   // Create a new reader for images of the desired size and format.
   media_status_t return_code = loader_.AImageReader_newWithUsage(