Move load progress tracking logic to the frame tree.

content/browser/frame_host/render_frame_host_impl.cc

Index: content/browser/frame_host/render_frame_host_impl.cc
diff --git a/content/browser/frame_host/render_frame_host_impl.cc b/content/browser/frame_host/render_frame_host_impl.cc
index a1bc386d83c40c0c86c04c97f1473f29059bc4f8..5656864c38f17ea9c6a1ca738075a5dc26b695ab 100644
--- a/content/browser/frame_host/render_frame_host_impl.cc
+++ b/content/browser/frame_host/render_frame_host_impl.cc
@@ -105,10 +105,6 @@ base::i18n::TextDirection WebTextDirectionToChromeTextDirection(
 
 }  // namespace
 
-const double RenderFrameHostImpl::kLoadingProgressNotStarted = 0.0;
-const double RenderFrameHostImpl::kLoadingProgressMinimum = 0.1;
-const double RenderFrameHostImpl::kLoadingProgressDone = 1.0;
-
 // static
 bool RenderFrameHostImpl::IsRFHStateActive(RenderFrameHostImplState rfh_state) {
   return rfh_state == STATE_DEFAULT;
@@ -155,7 +151,6 @@ RenderFrameHostImpl::RenderFrameHostImpl(SiteInstance* site_instance,
       is_waiting_for_beforeunload_ack_(false),
       unload_ack_is_for_navigation_(false),
       is_loading_(false),
-      loading_progress_(kLoadingProgressNotStarted),
       accessibility_reset_token_(0),
       accessibility_reset_count_(0),
       no_create_browser_accessibility_manager_for_testing_(false),