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Create test display and window only if needed
Introduce annotation UseTestDisplay so only the annotated test class and method will create the extra display and windows when setting up. This may reduce the presubmit time of WmTests by 30% (~20min). Test: atest WmTests Bug: 154655192 Change-Id: I6ffae4d285d24eac93807bf644b4f2c8c8563b44