Pass initial size and GPU preference via context attributes

content/renderer/renderer_blink_platform_impl.cc

 // Copyright (c) 2012 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/renderer/renderer_blink_platform_impl.h"
 
 #include <utility>
 
 #include "base/command_line.h"
 #include "base/files/file_path.h"
@@ skipping 1067 matching lines @@
 
   // This is an offscreen context, which doesn't use the default frame buffer,
   // so don't request any alpha, depth, stencil, antialiasing.
   gpu::gles2::ContextCreationAttribHelper attributes;
   attributes.alpha_size = -1;
   attributes.depth_size = 0;
   attributes.stencil_size = 0;
   attributes.samples = 0;
   attributes.sample_buffers = 0;
   attributes.bind_generates_resource = false;
+  // Prefer discrete GPU for WebGL.
+  attributes.gpu_preference = gl::PreferDiscreteGpu;
 
   attributes.fail_if_major_perf_caveat =
       web_attributes.failIfMajorPerformanceCaveat;
   DCHECK_GT(web_attributes.webGLVersion, 0u);
   DCHECK_LE(web_attributes.webGLVersion, 2u);
   if (web_attributes.webGLVersion == 2)
     attributes.context_type = gpu::gles2::CONTEXT_TYPE_WEBGL2;
   else
     attributes.context_type = gpu::gles2::CONTEXT_TYPE_WEBGL1;
 
   constexpr bool automatic_flushes = true;
   constexpr bool support_locking = false;
-  // Prefer discrete GPU for WebGL.
-  constexpr gl::GpuPreference gpu_preference = gl::PreferDiscreteGpu;
 
   scoped_refptr<ContextProviderCommandBuffer> provider(
       new ContextProviderCommandBuffer(
           std::move(gpu_channel_host), gpu::GPU_STREAM_DEFAULT,
           gpu::GpuStreamPriority::NORMAL, gpu::kNullSurfaceHandle,
-          GURL(top_document_web_url), gpu_preference, automatic_flushes,
-          support_locking, gpu::SharedMemoryLimits(), attributes, share_context,
+          GURL(top_document_web_url), automatic_flushes, support_locking,
+          gpu::SharedMemoryLimits(), attributes, share_context,
           command_buffer_metrics::OFFSCREEN_CONTEXT_FOR_WEBGL));
   return new WebGraphicsContext3DProviderImpl(std::move(provider));
 }
 
 //------------------------------------------------------------------------------
 
 blink::WebGraphicsContext3DProvider*
 RendererBlinkPlatformImpl::createSharedOffscreenGraphicsContext3DProvider() {
   scoped_refptr<ContextProviderCommandBuffer> provider =
       RenderThreadImpl::current()->SharedMainThreadContextProvider();
@@ skipping 190 matching lines @@
   return &trial_token_validator_;
 }
 
 void RendererBlinkPlatformImpl::workerContextCreated(
     const v8::Local<v8::Context>& worker) {
   GetContentClient()->renderer()->DidInitializeWorkerContextOnWorkerThread(
       worker);
 }
 
 }  // namespace content