Fix extensions compile issues for Android on sync_unit_tests.

chrome/chrome_browser.gypi

Index: chrome/chrome_browser.gypi
diff --git a/chrome/chrome_browser.gypi b/chrome/chrome_browser.gypi
index 68c7a533c98f83eb06cf0ed5e9747b5330d1b407..4ab9eedd485a4494ffb92b8d068b609f482771bc 100644
--- a/chrome/chrome_browser.gypi
+++ b/chrome/chrome_browser.gypi
@@ -2561,6 +2561,8 @@
         'browser/transport_security_persister.h',
         'browser/ui/alternate_error_tab_observer.cc',
         'browser/ui/alternate_error_tab_observer.h',
+        'browser/ui/android/extensions/extension_view_android.cc',
+        'browser/ui/android/extensions/extension_view_android.h',
         'browser/ui/app_modal_dialogs/app_modal_dialog.cc',
         'browser/ui/app_modal_dialogs/app_modal_dialog.h',
         'browser/ui/app_modal_dialogs/app_modal_dialog_queue.cc',
@@ -4684,14 +4686,12 @@
           ],
           'sources/': [
             ['exclude', '^browser/background/'],
-            ['exclude', '^browser/extensions/'],
             ['exclude', '^browser/notifications/'],
             ['exclude', '^browser/task_manager/'],
             ['exclude', '^browser/themes/'],
             ['exclude', '^browser/ui/panels/'],
             ['exclude', '^browser/ui/tabs/'],
             ['exclude', '^browser/ui/toolbar/'],
-            ['exclude', '^browser/ui/webui/extensions'],
             ['exclude', '^browser/ui/webui/options'],
             ['exclude', '^browser/ui/webui/options2'],
           ],