SF: Handle the empty hdr10plus metadata in setPerFrameMetadata

There was a case that Media enabled HDR10PLUS in validTypes without
passing any metadata.The patch handles the error to avoid the crash of
SurfaceFlinger.

Bug: 157868992
Test: atest android.mediav2.cts.CodecDecoderSurfaceTest
Change-Id: I57275672ef2fe8079e652094e77a0a50de10c5b9
diff --git a/services/surfaceflinger/DisplayHardware/ComposerHal.cpp b/services/surfaceflinger/DisplayHardware/ComposerHal.cpp
index dbdffec..a3f1b52 100644
--- a/services/surfaceflinger/DisplayHardware/ComposerHal.cpp
+++ b/services/surfaceflinger/DisplayHardware/ComposerHal.cpp
@@ -1676,6 +1676,7 @@
     if (found == mReturnData.end()) {
         outClientTargetProperty->pixelFormat = PixelFormat::RGBA_8888;
         outClientTargetProperty->dataspace = Dataspace::UNKNOWN;
+        return;
     }
 
     ReturnData& data = found->second;