Adding DRP specfic UMA for FirstContentfulPaint

content/test/test_web_contents.h

Index: content/test/test_web_contents.h
diff --git a/content/test/test_web_contents.h b/content/test/test_web_contents.h
index 0211bbf33049924f4bf15e7f7a748820c3b3b4ec..b65213379b12916d01c3a6733d64b7b872ef5db5 100644
--- a/content/test/test_web_contents.h
+++ b/content/test/test_web_contents.h
@@ -104,20 +104,24 @@ class TestWebContents : public WebContentsImpl, public WebContentsTester {
   // to |ExpectSetHistoryOffsetAndLength()|.
   void SetHistoryOffsetAndLength(int history_offset,
                                  int history_length) override;
 
   void TestDidFinishLoad(const GURL& url);
   void TestDidFailLoadWithError(const GURL& url,
                                 int error_code,
                                 const base::string16& error_description,
                                 bool was_ignored_by_handler);
 
+  void set_simulate_fetch_via_data_reduction_proxy(bool enabled) {
+    simulate_fetch_via_data_reduction_proxy_ = enabled;
+  }
+
  protected:
   // The deprecated WebContentsTester still needs to subclass this.
   explicit TestWebContents(BrowserContext* browser_context);
 
  private:
   // WebContentsImpl overrides
   void CreateNewWindow(
       SiteInstance* source_site_instance,
       int32_t route_id,
       int32_t main_frame_route_id,
@@ -139,15 +143,16 @@ class TestWebContents : public WebContentsImpl, public WebContentsTester {
                             const Referrer& referrer,
                             const std::string& headers) override;
 
   RenderViewHostDelegateView* delegate_view_override_;
 
   // Expectations for arguments of |SetHistoryOffsetAndLength()|.
   bool expect_set_history_offset_and_length_;
   int expect_set_history_offset_and_length_history_offset_;
   int expect_set_history_offset_and_length_history_length_;
   std::string save_frame_headers_;
+  bool simulate_fetch_via_data_reduction_proxy_;
 };
 
 }  // namespace content
 
 #endif  // CONTENT_TEST_TEST_WEB_CONTENTS_H_