add gm to show bug in stroked-text in drawPosText

gm/stroketext.cpp

+/*
+ * Copyright 2014 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"
+
+static void draw_text_stroked(SkCanvas* canvas, const SkPaint& paint) {
+    SkPaint p(paint);
+    SkPoint loc = { 20, 450 };
+    
+    canvas->drawText("P", 1, loc.fX, loc.fY - 225, p);
+    canvas->drawPosText("P", 1, &loc, p);
+    
+    p.setColor(SK_ColorRED);
+    p.setStyle(SkPaint::kStroke_Style);
+    p.setStrokeWidth(10);
+    
+    canvas->drawText("P", 1, loc.fX, loc.fY - 225, p);
+    canvas->drawPosText("P", 1, &loc, p);
+}
+
+class StrokeTextGM : public skiagm::GM {
+    // Skia has a threshold above which it draws text via paths instead of using scalercontext
+    // and caching the glyph. This GM wants to ensure that we draw stroking correctly on both
+    // sides of this threshold.
+    enum {
+        kBelowThreshold_TextSize = 255,
+        kAboveThreshold_TextSize = 257
+    };
+public:
+    StrokeTextGM() {}
+
+protected:
+    virtual SkString onShortName() SK_OVERRIDE {
+        return SkString("stroketext");
+    }
+
+    virtual SkISize onISize() SK_OVERRIDE {
+        return SkISize::Make(640, 480);
+    }
+
+    virtual void onDraw(SkCanvas* canvas) SK_OVERRIDE {
+        SkPaint paint;
+        paint.setAntiAlias(true);
+        
+        paint.setTextSize(kBelowThreshold_TextSize);
+        draw_text_stroked(canvas, paint);
+        
+        canvas->translate(200, 0);
+        paint.setTextSize(kAboveThreshold_TextSize);
+        draw_text_stroked(canvas, paint);
+    }
+
+private:
+    typedef skiagm::GM INHERITED;
+};
+
+DEF_GM( return SkNEW(StrokeTextGM); )