Extensions: Send the tab id to platform apps.

chrome/browser/extensions/api/media_galleries/media_galleries_api.cc

Index: chrome/browser/extensions/api/media_galleries/media_galleries_api.cc
===================================================================
--- chrome/browser/extensions/api/media_galleries/media_galleries_api.cc	(revision 246091)
+++ chrome/browser/extensions/api/media_galleries/media_galleries_api.cc	(working copy)
@@ -21,6 +21,7 @@
 #include "chrome/browser/extensions/api/file_system/file_system_api.h"
 #include "chrome/browser/extensions/blob_reader.h"
 #include "chrome/browser/extensions/extension_prefs.h"
+#include "chrome/browser/extensions/extension_tab_util.h"
 #include "chrome/browser/media_galleries/media_file_system_registry.h"
 #include "chrome/browser/media_galleries/media_galleries_dialog_controller.h"
 #include "chrome/browser/media_galleries/media_galleries_histograms.h"
@@ -412,8 +413,16 @@
   const std::string& app_id = GetExtension()->id();
   WebContents* contents = GetWebContents(render_view_host(), profile, app_id);
   if (!contents) {
-    SendResponse(false);
-    return;
+    // When the request originated from a background page, but there is no app
+    // window open, check to see if it originated from a tab and display the
+    // dialog in that tab.
+    bool found_tab = extensions::ExtensionTabUtil::GetTabById(
+        source_tab_id(), profile, profile->IsOffTheRecord(),
+        NULL, NULL, &contents, NULL);
+    if (!found_tab || !contents) {
+      SendResponse(false);
+      return;
+    }
   }
 
   if (!user_gesture()) {