PlzNavigate: add support in several navigation controller unit tests

content/browser/frame_host/navigation_request.h

Index: content/browser/frame_host/navigation_request.h
diff --git a/content/browser/frame_host/navigation_request.h b/content/browser/frame_host/navigation_request.h
index eb5372113741e6ee9bb5e6d2eefd21ef957c76d7..ff1614f27ab8c32bfab51d79bc52100714a8f1cc 100644
--- a/content/browser/frame_host/navigation_request.h
+++ b/content/browser/frame_host/navigation_request.h
@@ -27,6 +27,27 @@ struct NavigationRequestInfo;
 // the navigation following its refactoring.
 class CONTENT_EXPORT NavigationRequest : public NavigationURLLoaderDelegate {
  public:
+  // Keeps track of the various stages of a NavigationRequest.
+  enum NavigationState {
+    // Initial state.
+    NOT_STARTED = 0,
+
+    // Waiting for a BeginNavigation IPC from the renderer. If there is no live
+    // renderer when the request is created, this stage is skipped.

[nasko, 2014/12/17 19:55:38]

The no live renderer is only for browser-initiated navigations, right? Also,
when we optimize out roundtrip because no beforeunload handlers are registered,
we will skip it too, right?
Just want to make sure I understand it correctly.

[clamy, 2014/12/18 13:54:42]

This stage only happens in browser initiated navigations. Yes I think we will be
able to optimize this step out for cross-site navigations where the old page has
no BeforeUnload handler registered.

+    WAITING_FOR_RENDERER_RESPONSE,
+
+    // The request was sent to the IO thread.
+    STARTED,
+
+    // The response started on the IO thread and is ready to be committed. This
+    // is one of the two final states for the request.
+    RESPONSE_STARTED,
+
+    // The request failed on the IO thread and an error page should be
+    // displayed. This is one of the two final states for the request.
+    FAILED,
+  };
+
   NavigationRequest(FrameTreeNode* frame_tree_node,
                     const CommonNavigationParams& common_params,
                     const CommitNavigationParams& commit_params);
@@ -45,6 +66,12 @@ class CONTENT_EXPORT NavigationRequest : public NavigationURLLoaderDelegate {
 
   NavigationURLLoader* loader_for_testing() const { return loader_.get(); }
 
+  NavigationState state() const { return state_; }
+
+  void SetWaitingForRendererResponse() {
+    state_ = WAITING_FOR_RENDERER_RESPONSE;

[nasko, 2014/12/17 19:55:38]

nit: DCHECK we aren't already in this state?

[clamy, 2014/12/18 13:54:42]

In fact it is even DCHECK that the state is NOT_STARTED.

+  }
+
  private:
   // NavigationURLLoaderDelegate implementation.
   void OnRequestRedirected(
@@ -64,6 +91,8 @@ class CONTENT_EXPORT NavigationRequest : public NavigationURLLoaderDelegate {
   CommonNavigationParams common_params_;
   const CommitNavigationParams commit_params_;
 
+  NavigationState state_;
+
   scoped_ptr<NavigationURLLoader> loader_;
 
   DISALLOW_COPY_AND_ASSIGN(NavigationRequest);