Honor x-chrome header on non web triggerable transitions

Fixed a regression introduced in cl 488163003. Manual navigation, e.g. typing
url or clicking bookmark, is not considered user gesture. Thus with the cl
488163003, chrome will ignore x-chrome-manage-account header on manual
navigation to gaia endpoints. We should honor header on both non web
triggerable transitions and web triggerable transitions with user gesture.

BUG=394869

Review URL: https://codereview.chromium.org/481053003

Cr-Commit-Position: refs/heads/master@{#291518}
git-svn-id: svn://svn.chromium.org/chrome/trunk/src@291518 0039d316-1c4b-4281-b951-d872f2087c98

chrome/browser/signin/signin_header_helper.cc

@@ -256,7 +256,9 @@ void ProcessMirrorResponseHeaderIfExists(
 
   const content::ResourceRequestInfo* info =
       content::ResourceRequestInfo::ForRequest(request);
-  if (!(info && info->IsMainFrame() && info->HasUserGesture()))
+  if (!(info && info->IsMainFrame() &&
+        (info->HasUserGesture() ||
+         !content::PageTransitionIsWebTriggerable(info->GetPageTransition()))))
     return;
 
   std::string header_value;