SurfaceFlinger: fix color transfer test

Add support for color management in
LayerTransactionTest.SetColorTransformBasic.

If color management is enabled, some considerations are needed
for the expected color output.

Test: adb shell /data/nativetest64/SurfaceFlinger_test/SurfaceFlinger_test
Change-Id: I7be7d561e7683fd57db0519932c4c308a6350c0d
diff --git a/services/surfaceflinger/SurfaceFlinger.cpp b/services/surfaceflinger/SurfaceFlinger.cpp
index ab07bc6..fc8ca54 100644
--- a/services/surfaceflinger/SurfaceFlinger.cpp
+++ b/services/surfaceflinger/SurfaceFlinger.cpp
@@ -513,6 +513,10 @@
     return mDisplayTokens[id];
 }
 
+bool SurfaceFlinger::isColorManagementUsed() const {
+    return useColorManagement;
+}
+
 void SurfaceFlinger::bootFinished()
 {
     if (mStartPropertySetThread->join() != NO_ERROR) {
@@ -4744,6 +4748,7 @@
         case SET_TRANSACTION_STATE:
         // Creating a scoped connection is safe, as per discussion in ISurfaceComposer.h
         case CREATE_SCOPED_CONNECTION:
+        case IS_COLOR_MANAGEMET_USED:
         case GET_COMPOSITION_PREFERENCE: {
             return OK;
         }