Changes PlzNavitate histograms to try and simplify their multi-modal characteristic.

content/browser/frame_host/render_frame_host_impl.cc

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "content/browser/frame_host/render_frame_host_impl.h"
 
 #include "base/bind.h"
 #include "base/command_line.h"
 #include "base/containers/hash_tables.h"
 #include "base/lazy_instance.h"
@@ skipping 857 matching lines @@
         UMA_HISTOGRAM_TIMES(
             "InterProcessTimeTicks.BrowserBehind_RendererToBrowser", skew);
       } else {
         UMA_HISTOGRAM_TIMES(
             "InterProcessTimeTicks.BrowserAhead_RendererToBrowser", -skew);
       }
     }
     UMA_HISTOGRAM_BOOLEAN(
         "InterProcessTimeTicks.IsSkewAdditive_RendererToBrowser",
         is_skew_additive);
+
+    frame_tree_node_->navigator()->LogBeforeUnloadTime(
+      renderer_before_unload_start_time, renderer_before_unload_end_time);
   }
   frame_tree_node_->render_manager()->OnBeforeUnloadACK(
       unload_ack_is_for_cross_site_transition_, proceed,
       before_unload_end_time);
 
   // If canceled, notify the delegate to cancel its pending navigation entry.
   if (!proceed)
     render_view_host_->GetDelegate()->DidCancelLoading();
 }
 
@@ skipping 653 matching lines @@
   // Clear any state if a pending navigation is canceled or preempted.
   if (suspended_nav_params_)
     suspended_nav_params_.reset();
 
   TRACE_EVENT_ASYNC_END0("navigation",
                          "RenderFrameHostImpl navigation suspended", this);
   navigations_suspended_ = false;
 }
 
 }  // namespace content