Fixing guest processes to use the proper storage partition.

chrome/browser/chrome_content_browser_client.cc

Index: chrome/browser/chrome_content_browser_client.cc
diff --git a/chrome/browser/chrome_content_browser_client.cc b/chrome/browser/chrome_content_browser_client.cc
index c755dc03e2f75c23cfe5d7160613152a8f52ea71..796761483ff45673358afe90463c8e8fd6bce0e0 100644
--- a/chrome/browser/chrome_content_browser_client.cc
+++ b/chrome/browser/chrome_content_browser_client.cc
@@ -491,6 +491,9 @@ std::string ChromeContentBrowserClient::GetStoragePartitionIdForChildProcess(
 std::string ChromeContentBrowserClient::GetStoragePartitionIdForSite(
     content::BrowserContext* browser_context,
     const GURL& site) {
+  if (site.SchemeIs(chrome::kGuestScheme))
+    return "guest-" + site.host();
+
   const Extension* extension = NULL;
   Profile* profile = Profile::FromBrowserContext(browser_context);
   ExtensionService* extension_service =
@@ -1604,10 +1607,16 @@ void ChromeContentBrowserClient::OverrideWebkitPrefs(
   chrome::ViewType view_type = chrome::GetViewType(web_contents);
   ExtensionService* service = profile->GetExtensionService();
   if (service) {
-    const Extension* extension = service->extensions()->GetByID(
-        rvh->GetSiteInstance()->GetSiteURL().host());
-    extension_webkit_preferences::SetPreferences(
-        extension, view_type, web_prefs);
+    const GURL& url = rvh->GetSiteInstance()->GetSiteURL();
+    // Ensure that we are only granting extension preferences to URLs with the
+    // correct scheme. Without this check, guest:// schemes used by webview
+    // tags as well as hosts that happen to match the id of an install extension
+    // would get the wrong preferences.
+    if (url.SchemeIs(chrome::kExtensionScheme)) {
+      const Extension* extension = service->extensions()->GetByID(url.host());
+      extension_webkit_preferences::SetPreferences(
+          extension, view_type, web_prefs);
+    }
   }
 
   if (content::IsForceCompositingModeEnabled())