Modify --isolate-extensions to not isolate hosted apps.

content/browser/frame_host/render_frame_host_manager.cc

Index: content/browser/frame_host/render_frame_host_manager.cc
diff --git a/content/browser/frame_host/render_frame_host_manager.cc b/content/browser/frame_host/render_frame_host_manager.cc
index 3b4ae3a9baa445739568803a40184eafae88e94f..b7f8d14d21119f810e95e6c86c0fd7284cad4540 100644
--- a/content/browser/frame_host/render_frame_host_manager.cc
+++ b/content/browser/frame_host/render_frame_host_manager.cc
@@ -1516,8 +1516,8 @@ bool RenderFrameHostManager::IsRendererTransferNeededForNavigation(
   if (rfh->GetSiteInstance()->GetSiteURL().SchemeIs(kGuestScheme))
     return false;
 
-  GURL effective_url = SiteInstanceImpl::GetEffectiveURL(
-      rfh->GetSiteInstance()->GetBrowserContext(), dest_url);
+  BrowserContext* context = rfh->GetSiteInstance()->GetBrowserContext();
+  GURL effective_url = SiteInstanceImpl::GetEffectiveURL(context, dest_url);
 
   // TODO(nasko, nick): These following --site-per-process checks are
   // overly simplistic. Update them to match all the cases
@@ -1531,7 +1531,8 @@ bool RenderFrameHostManager::IsRendererTransferNeededForNavigation(
   // The sites differ. If either one requires a dedicated process,
   // then a transfer is needed.
   return rfh->GetSiteInstance()->RequiresDedicatedProcess() ||
-         SiteIsolationPolicy::DoesSiteRequireDedicatedProcess(effective_url);
+         SiteInstanceImpl::DoesSiteRequireDedicatedProcess(context,
+                                                           effective_url);
 }
 
 SiteInstance* RenderFrameHostManager::ConvertToSiteInstance(