Fix transitive dependencies on SkImageEncoder

In https://skia-review.googlesource.com/c/skia/+/512416,
we would like to decouple SkImage and SkImageEncoder. This CL
was created by searching for use of these objects:
 - SkEncodedImageFormat
 - SkStream
 - SkData
 - SkBitmap
 - SkPixmap

and making sure those files followed the Include What You Use
(IWYU) guidelines.

Signed-off-by: Kevin Lubick <kjlubick@google.com>
Change-Id: I8edbcd1c9a526b8084d7e2c023895d1ad2f8c9b1
diff --git a/libs/hwui/tests/common/TestUtils.h b/libs/hwui/tests/common/TestUtils.h
index 5092675..75865c7 100644
--- a/libs/hwui/tests/common/TestUtils.h
+++ b/libs/hwui/tests/common/TestUtils.h
@@ -27,10 +27,20 @@
 #include <renderstate/RenderState.h>
 #include <renderthread/RenderThread.h>
 
+#include <SkBitmap.h>
+#include <SkColor.h>
+#include <SkImageInfo.h>
+#include <SkRefCnt.h>
+
 #include <gtest/gtest.h>
 #include <memory>
 #include <unordered_map>
 
+class SkCanvas;
+class SkMatrix;
+class SkPath;
+struct SkRect;
+
 namespace android {
 namespace uirenderer {