Running an AWT/Swing applet in a browser renders InputMethods inoperable because raw key events are no longer sent to applets. This also breaks applets that rely on raw key events, so we need a means of selectively enabling IME in the plugin. This can't be done without some form of communication from AWT that IME is needed, otherwise either text entry is completely broken or raw key listeners are completely broken.

I propose adding a new InputMethod that when active tells the plugin that it needs IME to be activated.

JDK-8019883 will cover any changes needed in deployment.