Bug 1363290 - Part 3: Proxy win32's SetCursorPos for plugins in chrome process. r=jimm, r=jed

SetCursorPos is used by Flash's relative cursor motion behavior.  It is blocked by the plugin sandbox.  This patch allows it to run by proxying it on the main process.

dom/plugins/ipc/PluginModuleParent.cpp

@@ -3358,3 +3358,15 @@ PluginModuleChromeParent::AnswerGetFileName(const GetFileNameFunc& aFunc,
     return IPC_FAIL_NO_REASON(this);
 #endif
 }
+
+mozilla::ipc::IPCResult
+PluginModuleChromeParent::AnswerSetCursorPos(const int &x, const int &y,
+                                             bool* aResult)
+{
+#if defined(XP_WIN)
+    *aResult = ::SetCursorPos(x, y);
+    return IPC_OK();
+#else
+    return PluginModuleParent::AnswerSetCursorPos(x, y, aResult);
+#endif
+}