Use MemoryCoordinatorClientRegistry in BlinkPlatformImpl::requestPurgeMemory()

content/public/test/render_view_test.cc

Index: content/public/test/render_view_test.cc
diff --git a/content/public/test/render_view_test.cc b/content/public/test/render_view_test.cc
index c507a914ead48b1803d7b3ee9331756b22262314..f3857d4137679c21baa3e104be2a4f56024f1661 100644
--- a/content/public/test/render_view_test.cc
+++ b/content/public/test/render_view_test.cc
@@ -119,7 +119,7 @@ class RendererBlinkPlatformImplTestOverrideImpl
  public:
   RendererBlinkPlatformImplTestOverrideImpl(
       blink::scheduler::RendererScheduler* scheduler)
-      : RendererBlinkPlatformImpl(scheduler, nullptr, nullptr) {}
+      : RendererBlinkPlatformImpl(scheduler, nullptr) {}
 
   // Get rid of the dependency to the sandbox, which is not available in
   // RenderViewTest.