Stash taskbar when software keyboard is docked

Stash taskbar when
1) Software keybaord is docked
2) Input toolbar is placed at the taskbar area (stash so toolbar and taskbar would not overlap)

Testing result:
https://drive.google.com/file/d/1NMDexHl0FgyHFaOUh_GSEEUU2k08STJH/view?usp=sharing

Bug: 317251202
Test: TaplTestsQuickstep#testQuickSwitchToPreviousAppForTablet
Flag: N/A

Change-Id: I90662bc6e68f644e919f5c702059476b02519ed6

quickstep/tests/src/com/android/quickstep/TaplTestsQuickstep.java

@@ -347,7 +347,7 @@ public class TaplTestsQuickstep extends AbstractQuickStepTest {
             boolean isTransientTaskbar = mLauncher.isTransientTaskbar();
             // Expect task bar invisible when the launched app was the IME activity.
             LaunchedAppState launchedAppState = getAndAssertLaunchedApp();
-            if (!isTransientTaskbar && isHardwareKeyboard()) {
+            if (!isTransientTaskbar && isHardwareKeyboard() && !mLauncher.isImeDocked()) {
                 launchedAppState.assertTaskbarVisible();
             } else {
                 launchedAppState.assertTaskbarHidden();