Add a new API to create a surfaceless GLSurface for Ozone

content/common/gpu/media/rendering_helper.cc

Index: content/common/gpu/media/rendering_helper.cc
diff --git a/content/common/gpu/media/rendering_helper.cc b/content/common/gpu/media/rendering_helper.cc
index 45271f10501436cedbe223ccd84d6904ee0b6ccb..c3b2f9ef047db86d30b64387a03ebf0fbf38aa6b 100644
--- a/content/common/gpu/media/rendering_helper.cc
+++ b/content/common/gpu/media/rendering_helper.cc
@@ -366,7 +366,8 @@ void RenderingHelper::Initialize(const RenderingHelperParams& params,
     CHECK(fb_status == GL_FRAMEBUFFER_COMPLETE) << fb_status;
     glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
     glClear(GL_COLOR_BUFFER_BIT);
-    glBindFramebufferEXT(GL_FRAMEBUFFER, 0);
+    glBindFramebufferEXT(GL_FRAMEBUFFER,
+                         gl_surface_->GetBackingFrameBufferObject());
   }
 
   // These vertices and texture coords. map (0,0) in the texture to the
@@ -572,7 +573,8 @@ void RenderingHelper::RenderThumbnail(uint32 texture_target,
   glBindFramebufferEXT(GL_FRAMEBUFFER, thumbnails_fbo_id_);
   GLSetViewPort(area);
   RenderTexture(texture_target, texture_id);
-  glBindFramebufferEXT(GL_FRAMEBUFFER, 0);
+  glBindFramebufferEXT(GL_FRAMEBUFFER,
+                       gl_surface_->GetBackingFrameBufferObject());
 
   // Need to flush the GL commands before we return the tnumbnail texture to
   // the decoder.
@@ -663,7 +665,8 @@ void RenderingHelper::GetThumbnailsAsRGB(std::vector<unsigned char>* rgb,
                GL_RGBA,
                GL_UNSIGNED_BYTE,
                &rgba[0]);
-  glBindFramebufferEXT(GL_FRAMEBUFFER, 0);
+  glBindFramebufferEXT(GL_FRAMEBUFFER,
+                       gl_surface_->GetBackingFrameBufferObject());
   rgb->resize(num_pixels * 3);
   // Drop the alpha channel, but check as we go that it is all 0xff.
   bool solid = true;
@@ -700,7 +703,13 @@ void RenderingHelper::RenderContent() {
         static_cast<base::WaitableEvent*>(NULL)));
   }
 
-  glUniform1i(glGetUniformLocation(program_, "tex_flip"), 1);
+  int tex_flip = 1;
+#if USE_OZONE
+  // Ozone surfaceless renders flipped from normal GL, so there's no need to
+  // do an extra flip.
+  tex_flip = 0;
+#endif
+  glUniform1i(glGetUniformLocation(program_, "tex_flip"), tex_flip);
 
   // Frames that will be returned to the client (via the no_longer_needed_cb)
   // after this vector falls out of scope at the end of this method. We need