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 3b765a2c1b31ecebcf0297f0a3296960c74a392a..1a6dc0e62f53c251ad2ec61c136777aad607ee07 100644
--- a/chrome/chrome_browser.gypi
+++ b/chrome/chrome_browser.gypi
@@ -2569,6 +2569,8 @@
         'browser/ui/alternate_error_tab_observer.cc',
         'browser/ui/alternate_error_tab_observer.h',
         'browser/ui/android/certificate_viewer.cc',
+        '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',
@@ -4697,14 +4699,12 @@
           ],
           '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'],
           ],