Revert of rename SkCanvasDrawable to SkDrawable, and make public

src/core/SkCanvasDrawable.cpp

Index: src/core/SkCanvasDrawable.cpp
diff --git a/src/core/SkCanvasDrawable.cpp b/src/core/SkCanvasDrawable.cpp
new file mode 100644
index 0000000000000000000000000000000000000000..99a4996bc906190f7480bb14278185f688ebe095
--- /dev/null
+++ b/src/core/SkCanvasDrawable.cpp
@@ -0,0 +1,77 @@
+/*
+ * 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 "SkCanvas.h"
+#include "SkCanvasDrawable.h"
+#include "SkThread.h"
+
+static int32_t next_generation_id() {
+    static int32_t gCanvasDrawableGenerationID;
+
+    // do a loop in case our global wraps around, as we never want to
+    // return a 0
+    int32_t genID;
+    do {
+        genID = sk_atomic_inc(&gCanvasDrawableGenerationID) + 1;
+    } while (0 == genID);
+    return genID;
+}
+
+SkCanvasDrawable::SkCanvasDrawable() : fGenerationID(0) {}
+
+static void draw_bbox(SkCanvas* canvas, const SkRect& r) {
+    SkPaint paint;
+    paint.setStyle(SkPaint::kStroke_Style);
+    paint.setColor(0xFFFF7088);
+    canvas->drawRect(r, paint);
+    canvas->drawLine(r.left(), r.top(), r.right(), r.bottom(), paint);
+    canvas->drawLine(r.left(), r.bottom(), r.right(), r.top(), paint);
+}
+
+void SkCanvasDrawable::draw(SkCanvas* canvas) {
+    SkAutoCanvasRestore acr(canvas, true);
+    this->onDraw(canvas);
+
+    if (false) {
+        draw_bbox(canvas, this->getBounds());
+    }
+}
+
+SkPicture* SkCanvasDrawable::newPictureSnapshot() {
+    return this->onNewPictureSnapshot();
+}
+
+uint32_t SkCanvasDrawable::getGenerationID() {
+    if (0 == fGenerationID) {
+        fGenerationID = next_generation_id();
+    }
+    return fGenerationID;
+}
+
+SkRect SkCanvasDrawable::getBounds() {
+    return this->onGetBounds();
+}
+
+void SkCanvasDrawable::notifyDrawingChanged() {
+    fGenerationID = 0;
+}
+
+/////////////////////////////////////////////////////////////////////////////////////////
+
+#include "SkPictureRecorder.h"
+
+SkPicture* SkCanvasDrawable::onNewPictureSnapshot() {
+    SkPictureRecorder recorder;
+
+    const SkRect bounds = this->getBounds();
+    SkCanvas* canvas = recorder.beginRecording(bounds, NULL, 0);
+    this->draw(canvas);
+    if (false) {
+        draw_bbox(canvas, bounds);
+    }
+    return recorder.endRecording();
+}