Add the IME insets to virtual display for bubble

This patch will add a fake IME window to virtual display when IME is
showing and covering a bubble window. Without the fake window, the
bubble will not receive the correct IME insets.

To do that, this patch:
1. Added an interface in ActivityView to get VirtualDisplay when needed,
   in order to create the display context.
2. Modify the visibility update. When the target is not a client
   controlled target, we ignore the client visibility. We also call
   visibility update when the control target updated.
3. With the modified infra, add the window with correct param and
   context.

Bug: 150780413
Test: atest WmTests:DisplayPolicyLayoutTests
Test: atest InsetsStateTest
Test: atest InsetsPolicyTest
Test: go/wm-smoke
Test: See reproduce steps in the bug

Change-Id: I52691b5c7f81261de580bb4fc762e88486e78141