Add missing return in GrYUVABackendTextureInfo

Bug: chromium:1374713
Change-Id: Id664ef65d583561060dc2aaeb827289a87d47886
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/593196
Commit-Queue: Brian Salomon <bsalomon@google.com>
Auto-Submit: Greg Daniel <egdaniel@google.com>
Reviewed-by: Brian Salomon <bsalomon@google.com>
diff --git a/src/gpu/ganesh/GrYUVABackendTextures.cpp b/src/gpu/ganesh/GrYUVABackendTextures.cpp
index 66743df..ea33141 100644
--- a/src/gpu/ganesh/GrYUVABackendTextures.cpp
+++ b/src/gpu/ganesh/GrYUVABackendTextures.cpp
@@ -45,6 +45,7 @@
         if (numActualChannels < numRequiredChannels) {
             *this = {};
             SkASSERT(!this->isValid());
+            return;
         }
         fPlaneFormats[i] = formats[i];
     }