Added new arguments for screenshot request

Added frameScaleX and frameScaleY to replace frameScale to allow callers
to specify an X and Y scale separately.

Added grayscale flag to allow the caller to take the screenshot
in grayscale.

Test: ScreenCaptureTest.CaptureWithGrayscale
Bug: 155825630
Change-Id: Iea043b7074707df897d80bf057d7cc3870afad89
diff --git a/services/surfaceflinger/tests/unittests/TestableSurfaceFlinger.h b/services/surfaceflinger/tests/unittests/TestableSurfaceFlinger.h
index 2701f47..eda8d79 100644
--- a/services/surfaceflinger/tests/unittests/TestableSurfaceFlinger.h
+++ b/services/surfaceflinger/tests/unittests/TestableSurfaceFlinger.h
@@ -353,7 +353,8 @@
                                 bool regionSampling) {
         ScreenCaptureResults captureResults;
         return mFlinger->renderScreenImplLocked(renderArea, traverseLayers, buffer, forSystem,
-                                                regionSampling, captureResults);
+                                                regionSampling, false /* grayscale */,
+                                                captureResults);
     }
 
     auto traverseLayersInLayerStack(ui::LayerStack layerStack, int32_t uid,