Made full screen video with DevTools not flash black on Android.

content/common/gpu/media/android_deferred_rendering_backing_strategy.cc

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/common/gpu/media/android_deferred_rendering_backing_strategy.h"
 
 #include <EGL/egl.h>
 #include <EGL/eglext.h>
 
 #include "base/android/build_info.h"
@@ skipping 82 matching lines @@
   if (service_id > 0 && have_context)
     glDeleteTextures(1, &service_id);
 }
 
 scoped_refptr<gfx::SurfaceTexture>
 AndroidDeferredRenderingBackingStrategy::GetSurfaceTexture() const {
   return surface_texture_;
 }
 
 uint32_t AndroidDeferredRenderingBackingStrategy::GetTextureTarget() const {
-  return GL_TEXTURE_EXTERNAL_OES;
+  // If we're using a surface texture, then we need an external texture target
+  // to sample from it.  If not, then we'll use 2D transparent textures to draw
+  // a transparent hole through which to see the SurfaceView.  This is normally
+  // needed only for the devtools inspector, since the overlay mechanism handles
+  // it otherwise.
+  return (surface_texture_ ? GL_TEXTURE_EXTERNAL_OES : GL_TEXTURE_2D);

[DaleCurtis, 2016/03/28 18:02:02]

No unnecessary parens.

[liberato (no reviews please), 2016/03/28 20:58:17]

Done.

 }
 
 AVDACodecImage* AndroidDeferredRenderingBackingStrategy::GetImageForPicture(
     const media::PictureBuffer& picture_buffer) {
   gpu::gles2::TextureRef* texture_ref =
       state_provider_->GetTextureForPicture(picture_buffer);
   RETURN_NULL_IF_NULL(texture_ref);
   gl::GLImage* image =
       texture_ref->texture()->GetLevelImage(GetTextureTarget(), 0);
   return static_cast<AVDACodecImage*>(image);
@@ skipping 57 matching lines @@
   AVDACodecImage* avda_image = GetImageForPicture(picture_buffer);
   RETURN_IF_NULL(avda_image);
   DCHECK_EQ(avda_image->GetMediaCodecBufferIndex(), -1);
   // Note that this is not a race, since we do not re-use a PictureBuffer
   // until after the CC is done drawing it.
   avda_image->SetMediaCodecBufferIndex(codec_buf_index);
   avda_image->SetSize(state_provider_->GetSize());
 }
 
 void AndroidDeferredRenderingBackingStrategy::AssignOnePictureBuffer(
-    const media::PictureBuffer& picture_buffer) {
+    const media::PictureBuffer& picture_buffer,
+    bool have_context) {
   // Attach a GLImage to each texture that will use the surface texture.
   // We use a refptr here in case SetImageForPicture fails.
   scoped_refptr<gpu::gles2::GLStreamTextureImage> gl_image =
       new AVDACodecImage(shared_state_, media_codec_,
                          state_provider_->GetGlDecoder(), surface_texture_);
   SetImageForPicture(picture_buffer, gl_image);
+
+  if (!surface_texture_ && have_context) {
+    // To make devtools work, we're using a 2D texture.  Make it transparent,
+    // so that it draws a hole for the SV to show through.  This is only
+    // because devtools draws and reads back, which skips overlay processing.
+    // It's unclear why devtools renders twice -- once normally, and once
+    // including a readback layer.  The result is that the device screen
+    // flashes as we alternately draw the overlay hole and this texture,
+    // unless we make the texture transparent.
+    unsigned char rgba[] = {0, 0, 0, 0};

[DaleCurtis, 2016/03/28 18:02:02]

static const, does uint8_t work?

[liberato (no reviews please), 2016/03/28 20:58:17]

Done.

+    const gfx::Size size(1, 1);

[DaleCurtis, 2016/03/28 18:02:02]

I'd just inline each value, but up to you.

[liberato (no reviews please), 2016/03/28 20:58:17]

i think that it's clearer than glTexImage2D(..., 1, 1, 0, GL_RGBA,...), so i'll
keep it as is.

+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, size.width(), size.height(), 0,
+                 GL_RGBA, GL_UNSIGNED_BYTE, rgba);
+  }
 }
 
 void AndroidDeferredRenderingBackingStrategy::ReleaseCodecBufferForPicture(
     const media::PictureBuffer& picture_buffer) {
   AVDACodecImage* avda_image = GetImageForPicture(picture_buffer);
 
   // See if there is a media codec buffer still attached to this image.
   const int32_t codec_buffer = avda_image->GetMediaCodecBufferIndex();
 
   if (codec_buffer >= 0) {
@@ skipping 163 matching lines @@
           base::ToLowerASCII(base::android::BuildInfo::GetInstance()->model()));
       if (model.find("a114") != std::string::npos)
         surface_texture_detach_works = false;
     }
   }
 
   return surface_texture_detach_works;
 }
 
 }  // namespace content