CLONE -Compiler error in mobile project after compiling a web project

Steps to reproduce:
1. Create a Flex Mobile project
2. Write code to reference something ONLY in airglobal.swc and compile (e.g. "var test:uint = Keyboard.SEARCH;")
3. Create a Flex WEB project
4. Go back to the Flex Mobile project, make a no-op change to force a recompile

Actual Results:
Compiler error
1119: Access of possibly undefined property SEARCH through a reference with static type Class.

Expected Results:
No error.

Workaround (if any):
Restart FB. It appears that the compiler cache got wedged with playerglobal.swc and can't restore airglobal.swc.