Set the custom app icon for devtools in BrowserView::GetWindowIcon()

The purpose of this CL is to reduce the number of places which set the
NavigationEntry's favicon data

BUG=517089
TEST=None

Review URL: https://codereview.chromium.org/1271303003

Cr-Commit-Position: refs/heads/master@{#342667}

chrome/browser/devtools/devtools_ui_bindings.cc

@@ -32,7 +32,6 @@
 #include "components/infobars/core/confirm_infobar_delegate.h"
 #include "components/infobars/core/infobar.h"
 #include "components/ui/zoom/page_zoom.h"
-#include "content/public/browser/favicon_status.h"
 #include "content/public/browser/invalidate_type.h"
 #include "content/public/browser/navigation_controller.h"
 #include "content/public/browser/navigation_entry.h"
@@ -391,12 +390,6 @@ DevToolsUIBindings::DevToolsUIBindings(content::WebContents* web_contents)
   extensions::ChromeExtensionWebContentsObserver::CreateForWebContents(
       web_contents_);
 
-  // Wipe out page icon so that the default application icon is used.
-  content::NavigationEntry* entry =
-      web_contents_->GetController().GetActiveEntry();
-  entry->GetFavicon().image = gfx::Image();
-  entry->GetFavicon().valid = true;
-
   // Register on-load actions.
   embedder_message_dispatcher_.reset(
       DevToolsEmbedderMessageDispatcher::CreateForDevToolsFrontend(this));

chrome/browser/ui/views/frame/browser_view.cc

@@ -1692,6 +1692,10 @@ gfx::ImageSkia BrowserView::GetWindowAppIcon() {
 }
 
 gfx::ImageSkia BrowserView::GetWindowIcon() {
+  // Use the default icon for devtools.
+  if (browser_->is_devtools())
+    return gfx::ImageSkia();
+
   if (browser_->is_app() || browser_->is_type_popup())
     return browser_->GetCurrentPageIcon().AsImageSkia();
   return gfx::ImageSkia();