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

content/public/browser/content_browser_client.h

 // Copyright (c) 2012 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.
 
 #ifndef CONTENT_PUBLIC_BROWSER_CONTENT_BROWSER_CLIENT_H_
 #define CONTENT_PUBLIC_BROWSER_CONTENT_BROWSER_CLIENT_H_
 
 #include <map>
 #include <string>
 #include <utility>
@@ skipping 162 matching lines @@
   // Get the effective URL for the given actual URL, to allow an embedder to
   // group different url schemes in the same SiteInstance.
   virtual GURL GetEffectiveURL(BrowserContext* browser_context,
                                const GURL& url);
 
   // Returns whether all instances of the specified effective URL should be
   // rendered by the same process, rather than using process-per-site-instance.
   virtual bool ShouldUseProcessPerSite(BrowserContext* browser_context,
                                        const GURL& effective_url);
 
+  // Returns true if site isolation should be enabled for |effective_url|. This
+  // call allows the embedder to supplement the site isolation policy enforced
+  // by the content layer.
+  //
+  // Will only be called if both of the following happen:
+  //   1. The embedder asked to be consulted, by returning true from
+  //      ContentClient::IsSupplementarySiteIsolationModeEnabled().
+  //   2. The content layer didn't decide to isolate |effective_url| according
+  //      to its internal policy (e.g. because of --site-per-process).
+  virtual bool DoesSiteRequireDedicatedProcess(BrowserContext* browser_context,
+                                               const GURL& effective_url);
+
   // Returns true unless the effective URL is part of a site that cannot live in
-  // a process dedicated to that site.  This is only called if
-  // SiteIsolationPolicy::DoesSiteRequireDedicatedProcess returns true.
+  // a process restricted to just that site.  This is only called if site
+  // isolation is enabled for this URL, and is a bug workaround.
+  //
   // TODO(nick): Remove this function once https://crbug.com/160576 is fixed,
   // and origin lock can be applied to all URLs.
   virtual bool ShouldLockToOrigin(BrowserContext* browser_context,
                                   const GURL& effective_url);
 
   // Returns a list additional WebUI schemes, if any.  These additional schemes
   // act as aliases to the chrome: scheme.  The additional schemes may or may
   // not serve specific WebUI pages depending on the particular URLDataSource
   // and its override of URLDataSource::ShouldServiceRequest. For all schemes
   // returned here, view-source is allowed.
@@ skipping 524 matching lines @@
   // Allows an embedder to provide its own ExternalVideoSurfaceContainer
   // implementation.  Return nullptr to disable external surface video.
   virtual ExternalVideoSurfaceContainer*
   OverrideCreateExternalVideoSurfaceContainer(WebContents* web_contents);
 #endif
 };
 
 }  // namespace content
 
 #endif  // CONTENT_PUBLIC_BROWSER_CONTENT_BROWSER_CLIENT_H_