Fix WIC encoder to support kJPEG_Type

(1) Add support for kJPEG to WIC
(2) Add encoding test.
(3) Turn on WIC jpeg encoder on Windows and CG jpeg
    encoder on Mac.

A follow-up may make Skia's encoders the default on all
platforms.  But, in order to do that, I think we need
to write better encoding unit tests for CG and WIC.

BUG=skia:3969
BUG=skia:5632
GOLD_TRYBOT_URL= https://gold.skia.org/search?issue=2245453002

Committed: https://skia.googlesource.com/skia/+/b3a7ef1fc0adc24859d2498aee54d3ec2cbcac3a
Review-Url: https://codereview.chromium.org/2245453002
diff --git a/gm/encode.cpp b/gm/encode.cpp
new file mode 100644
index 0000000..0cd562a
--- /dev/null
+++ b/gm/encode.cpp
@@ -0,0 +1,48 @@
+/*
+ * Copyright 2011 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+#include "gm.h"
+#include "SkCanvas.h"
+#include "SkData.h"
+#include "SkImageEncoder.h"
+#include "Resources.h"
+
+namespace skiagm {
+
+class EncodeGM : public GM {
+public:
+    EncodeGM() {}
+
+protected:
+    SkString onShortName() override {
+        return SkString("encode");
+    }
+
+    SkISize onISize() override {
+        return SkISize::Make(1024, 600);
+    }
+
+    void onDraw(SkCanvas* canvas) override {
+        SkBitmap orig;
+        GetResourceAsBitmap("mandrill_512_q075.jpg", &orig);
+        sk_sp<SkData> pngData(SkImageEncoder::EncodeData(orig, SkImageEncoder::kPNG_Type, 100));
+        sk_sp<SkData> jpegData(SkImageEncoder::EncodeData(orig, SkImageEncoder::kJPEG_Type, 100));
+
+        sk_sp<SkImage> pngImage = SkImage::MakeFromEncoded(pngData);
+        sk_sp<SkImage> jpegImage = SkImage::MakeFromEncoded(jpegData);
+        canvas->drawImage(pngImage.get(), 0.0f, 0.0f);
+        canvas->drawImage(jpegImage.get(), 512.0f, 0.0f);
+
+        const char text[] = "Images should look identical.";
+        canvas->drawText(text, sizeof(text) - 1, 450.0f, 550.0f, SkPaint());
+    }
+
+private:
+    typedef GM INHERITED;
+};
+
+DEF_GM( return new EncodeGM; )
+}