Fix usage of KeyEvent modifiers in input method session

In [1] we started using KeyEvent#hasModifiers() when the intention
was to check if any mentioned key modifier is used. The correct usage
would be directly checking for those modifiers e.g.# isCtrlPressed()

[1]: I6589cc73839acb6b2c3f9256c664b5db7e1ade8a

Fix: 380317043
Test: atest CtsInputMethodTestCases InputMethodServiceTest
Flag: android.view.inputmethod.verify_key_event
Change-Id: I69cb41d805f5b64f90f8a7c53b0e867a03c94b3e