services/ui: Split GpuServiceInternal into gpu vs. ws pieces.

services/ui/ws/test_utils.cc

Index: services/ui/ws/test_utils.cc
diff --git a/services/ui/ws/test_utils.cc b/services/ui/ws/test_utils.cc
index 9e1c7c0b1b4889a483e15107399012a3a24c415d..82cfd9c73151f989c8c406bf3c4bce1901122d1b 100644
--- a/services/ui/ws/test_utils.cc
+++ b/services/ui/ws/test_utils.cc
@@ -66,6 +66,8 @@ class TestPlatformDisplay : public PlatformDisplay {
       std::unique_ptr<cc::CopyOutputRequest> output_request) override {}
   gfx::Rect GetBounds() const override { return display_metrics_.bounds; }
   bool IsPrimaryDisplay() const override { return is_primary_; }
+  void OnGpuChannelEstablished(
+      scoped_refptr<gpu::GpuChannelHost> host) override {}
 
  private:
   ViewportMetrics display_metrics_;