Gesture Nav: Protect against the case when navigation completes as soon as it is requested.

content/browser/web_contents/aura/overscroll_navigation_overlay.cc

 // Copyright 2014 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/web_contents/aura/overscroll_navigation_overlay.h"
 
 #include <utility>
 #include <vector>
 
 #include "base/i18n/rtl.h"
@@ skipping 205 matching lines @@
 void OverscrollNavigationOverlay::OnOverscrollCompleted(
     std::unique_ptr<aura::Window> window) {
   DCHECK(direction_ != NONE);
   aura::Window* main_window = GetMainWindow();
   if (!main_window) {
     UMA_HISTOGRAM_ENUMERATION(
         "Overscroll.Cancelled", direction_, NAVIGATION_COUNT);
     return;
   }
 
+  main_window->SetTransform(gfx::Transform());
+  window_ = std::move(window);
+  // Make sure the window is in its default position.
+  window_->SetBounds(gfx::Rect(web_contents_window_->bounds().size()));
+  window_->SetTransform(gfx::Transform());
+  // Make sure the overlay window is on top.
+  web_contents_window_->StackChildAtTop(window_.get());
+
   // Make sure we can navigate first, as other factors can trigger a navigation
   // during an overscroll gesture and navigating without history produces a
   // crash.
   bool navigated = false;
   if (direction_ == FORWARD && web_contents_->GetController().CanGoForward()) {
     web_contents_->GetController().GoForward();
     navigated = true;
   } else if (direction_ == BACK && web_contents_->GetController().CanGoBack()) {
     web_contents_->GetController().GoBack();
     navigated = true;
   } else {
     // We need to dismiss the overlay without navigating as soon as the
     // overscroll finishes.
     UMA_HISTOGRAM_ENUMERATION(
         "Overscroll.Cancelled", direction_, NAVIGATION_COUNT);
     loading_complete_ = true;
   }
 
   if (navigated) {
     UMA_HISTOGRAM_ENUMERATION(
         "Overscroll.Navigated2", direction_, NAVIGATION_COUNT);
     StartObserving();
   }
 
-  main_window->SetTransform(gfx::Transform());
-  window_ = std::move(window);
-  // Make sure the window is in its default position.
-  window_->SetBounds(gfx::Rect(web_contents_window_->bounds().size()));
-  window_->SetTransform(gfx::Transform());
-  // Make sure the overlay window is on top.
-  web_contents_window_->StackChildAtTop(window_.get());
   direction_ = NONE;
   StopObservingIfDone();
 }
 
 void OverscrollNavigationOverlay::OnOverscrollCancelled() {
   UMA_HISTOGRAM_ENUMERATION(
       "Overscroll.Cancelled", direction_, NAVIGATION_COUNT);
   aura::Window* main_window = GetMainWindow();
   if (!main_window)
     return;
@@ skipping 14 matching lines @@
 
 void OverscrollNavigationOverlay::DidStopLoading() {
   // Don't compare URLs in this case - it's possible they won't match if
   // a gesture-nav initiated navigation was interrupted by some other in-site
   // navigation (e.g., from a script, or from a bookmark).
   loading_complete_ = true;
   StopObservingIfDone();
 }
 
 }  // namespace content