[DevTools] migrate InspectorPageAgent and InspectorMemoryAgent to new style

third_party/WebKit/Source/core/inspector/InspectorMemoryAgent.h

Index: third_party/WebKit/Source/core/inspector/InspectorMemoryAgent.h
diff --git a/third_party/WebKit/Source/core/inspector/InspectorMemoryAgent.h b/third_party/WebKit/Source/core/inspector/InspectorMemoryAgent.h
index b3445150ae1bef02bf353f69ea525c8e2074a173..a22a97284c0b64e3f89d74bc0f2123c64a02c636 100644
--- a/third_party/WebKit/Source/core/inspector/InspectorMemoryAgent.h
+++ b/third_party/WebKit/Source/core/inspector/InspectorMemoryAgent.h
@@ -45,10 +45,9 @@ class CORE_EXPORT InspectorMemoryAgent final
   static InspectorMemoryAgent* create() { return new InspectorMemoryAgent(); }
   ~InspectorMemoryAgent() override;
 
-  void getDOMCounters(ErrorString*,
-                      int* documents,
-                      int* nodes,
-                      int* jsEventListeners) override;
+  Response getDOMCounters(int* documents,
+                          int* nodes,
+                          int* jsEventListeners) override;
 
  private:
   InspectorMemoryAgent();