[NOT FOR REVIEW] extensions-wm: Add experimental extension API for window management.

chrome/common/extensions/permissions/api_permission.cc

Index: chrome/common/extensions/permissions/api_permission.cc
diff --git a/chrome/common/extensions/permissions/api_permission.cc b/chrome/common/extensions/permissions/api_permission.cc
index 42010d874da51a25307efe42c329b82356c9b871..cd5f73f674af204c71142eaab880f60d5ab46eaa 100644
--- a/chrome/common/extensions/permissions/api_permission.cc
+++ b/chrome/common/extensions/permissions/api_permission.cc
@@ -6,6 +6,7 @@
 
 #include "chrome/common/extensions/permissions/permissions_info.h"
 #include "chrome/common/extensions/permissions/socket_permission.h"
+#include "grit/chromium_strings.h"
 #include "grit/generated_resources.h"
 #include "ui/base/l10n/l10n_util.h"
 
@@ -155,6 +156,8 @@ void APIPermission::RegisterAllPermissions(
       PermissionMessage::kGeolocation },
     { kNotification, "notifications" },
     { kUnlimitedStorage, "unlimitedStorage", kFlagCannotBeOptional },
+    { kWM, "wm", kFlagNone, IDS_EXTENSION_PROMPT_WARNING_WM,
+      PermissionMessage::kWindowManager },
 
     // Register hosted and packaged app permissions.
     { kAppNotifications, "appNotifications" },