SF: Add DisplayDevice::initiateModeChange

This CL creates DisplayDevice::initiateModeChange which calls
HWC::setActiveConfigWithConstraints. SF should call DisplayDevice
instead of directly calling HWComposer.
This is a step towards removing the cached display modes from
the HWComposer class.

Test: presubmit
Bug: 159590486
Change-Id: Id05d2eacbbb6ed335fe205231b85e8af9a8ccd91
diff --git a/services/surfaceflinger/CompositionEngine/tests/MockHWComposer.h b/services/surfaceflinger/CompositionEngine/tests/MockHWComposer.h
index 4d36f0c..3133e90 100644
--- a/services/surfaceflinger/CompositionEngine/tests/MockHWComposer.h
+++ b/services/surfaceflinger/CompositionEngine/tests/MockHWComposer.h
@@ -96,7 +96,7 @@
     MOCK_CONST_METHOD1(isVsyncPeriodSwitchSupported, bool(PhysicalDisplayId));
     MOCK_CONST_METHOD1(getDisplayVsyncPeriod, nsecs_t(PhysicalDisplayId));
     MOCK_METHOD4(setActiveModeWithConstraints,
-                 status_t(PhysicalDisplayId, DisplayModeId,
+                 status_t(PhysicalDisplayId, hal::HWConfigId,
                           const hal::VsyncPeriodChangeConstraints&,
                           hal::VsyncPeriodChangeTimeline*));
     MOCK_METHOD2(setAutoLowLatencyMode, status_t(PhysicalDisplayId, bool));