cc, gpu: Use RGBA when using msaa on systems that don't support BGRA

cc/raster/gpu_tile_task_worker_pool.cc

Index: cc/raster/gpu_tile_task_worker_pool.cc
diff --git a/cc/raster/gpu_tile_task_worker_pool.cc b/cc/raster/gpu_tile_task_worker_pool.cc
index a79b880b563c8570765726751e3412749650307a..f2806c4e06a1382de97bf820a9b60c25e1e02c41 100644
--- a/cc/raster/gpu_tile_task_worker_pool.cc
+++ b/cc/raster/gpu_tile_task_worker_pool.cc
@@ -207,8 +207,13 @@ void GpuTileTaskWorkerPool::CheckForCompletedTasks() {
   completed_tasks_.clear();
 }
 
-ResourceFormat GpuTileTaskWorkerPool::GetResourceFormat() {
-  return rasterizer_->resource_provider()->best_texture_format();
+ResourceFormat GpuTileTaskWorkerPool::GetResourceFormat() const {
+  return rasterizer_->resource_provider()->best_render_buffer_format();
+}
+
+bool GpuTileTaskWorkerPool::GetResourceRequiresSwizzle() const {
+  // This doesn't require a swizzle because we rasterize to the correct format.
+  return false;
 }
 
 void GpuTileTaskWorkerPool::CompleteTasks(const Task::Vector& tasks) {