[PageLoadMetrics] Remove legacy IPC from Page Load Metrics.

chrome/browser/page_load_metrics/metrics_web_contents_observer.h

Index: chrome/browser/page_load_metrics/metrics_web_contents_observer.h
diff --git a/chrome/browser/page_load_metrics/metrics_web_contents_observer.h b/chrome/browser/page_load_metrics/metrics_web_contents_observer.h
index a57a65e5963f410332c9f94f0528175069734f9d..69eedb230884d27fb3c21fb20ff7e85ba4b44e7b 100644
--- a/chrome/browser/page_load_metrics/metrics_web_contents_observer.h
+++ b/chrome/browser/page_load_metrics/metrics_web_contents_observer.h
@@ -29,10 +29,6 @@ class NavigationHandle;
 class RenderFrameHost;
 }  // namespace content
 
-namespace IPC {
-class Message;
-}  // namespace IPC
-
 namespace page_load_metrics {
 
 class PageLoadMetricsEmbedderInterface;
@@ -53,15 +49,12 @@ class MetricsWebContentsObserver
   // have been observed.
   class TestingObserver {
    public:
-    enum class IPCType { LEGACY, MOJO };
-
     explicit TestingObserver(content::WebContents* web_contents);
     virtual ~TestingObserver();
 
     void OnGoingAway();
 
     virtual void OnCommit(PageLoadTracker* tracker) {}
-    virtual void DidReceiveTimingUpdate(IPCType type) {}
 
    private:
     page_load_metrics::MetricsWebContentsObserver* observer_;
@@ -81,8 +74,6 @@ class MetricsWebContentsObserver
   ~MetricsWebContentsObserver() override;
 
   // content::WebContentsObserver implementation:
-  bool OnMessageReceived(const IPC::Message& message,
-                         content::RenderFrameHost* render_frame_host) override;
   void DidFinishNavigation(
       content::NavigationHandle* navigation_handle) override;
   void DidRedirectNavigation(
@@ -152,11 +143,6 @@ class MetricsWebContentsObserver
   void UpdateTiming(mojom::PageLoadTimingPtr timing,
                     mojom::PageLoadMetadataPtr metadata) override;
 
-  // Called from legacy IPC.
-  void OnUpdateTimingOverIPC(content::RenderFrameHost* render_frame_host,
-                             const mojom::PageLoadTiming& timing,
-                             const mojom::PageLoadMetadata& metadata);
-
   void HandleFailedNavigationForTrackedLoad(
       content::NavigationHandle* navigation_handle,
       std::unique_ptr<PageLoadTracker> tracker);