IDEA-154620 ui: fix handling of shortcuts with second stroke for local actions

We need `myFoundComponent` to survive till the next action event, because is is used to find local actions (registered with `registerWithCustomShortcutSet`) in `inSecondStrokeInProgressState`.
It is a WeakReference, so this will not cause memory leaks.

It was broken in 9b6176d

platform/platform-impl/src/com/intellij/openapi/keymap/impl/KeyProcessorContext.java

@@ -98,6 +98,5 @@ public class KeyProcessorContext {
     myActions.clear();
     myFocusOwner = null;
     myDataContext = null;
-    myFoundComponent = null;
   }
 }