[Android WebView] Implement the capture picture API.

android_webview/public/browser/draw_sw.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef ANDROID_WEBVIEW_PUBLIC_BROWSER_DRAW_SW_H_
 #define ANDROID_WEBVIEW_PUBLIC_BROWSER_DRAW_SW_H_
 
 #include <jni.h>
 #include <stddef.h>
 
 #ifndef __cplusplus
 #error "Can't mix C and C++ when using jni.h"
 #endif
 
+class SkPicture;
+
 // Holds the information required to implement the SW draw to system canvas.
 struct AwPixelInfo {
   int config;         // In SkBitmap::Config format.
   int width;          // In pixels.
   int height;         // In pixels.
   int row_bytes;      // Number of bytes from start of one line to next.
   void* pixels;       // The pixels, all (height * row_bytes) of them.
   float matrix[9];    // The matrix currently in effect on the canvas.
   void* clip_region;  // Flattened clip region.
   size_t clip_region_size;   // Number of bytes in |clip_region|.
 };
 
 // Function that can be called to fish out the underlying native pixel data
 // from a Java canvas object, for optimized rendering path.
 // Returns the pixel info on success, which must be freed via a call to
 // AwReleasePixelsFunction, or NULL.
 typedef AwPixelInfo* (AwAccessPixelsFunction)(JNIEnv* env, jobject canvas);
 
 // Must be called to balance every *successful* call to AwAccessPixelsFunction
 // (i.e. that returned true).
 typedef void (AwReleasePixelsFunction)(AwPixelInfo* pixels);
 
+// Called to create an Android Picture object encapsulating a native SkPicture.
+typedef jobject (AwCreatePictureFunction)(JNIEnv* env, SkPicture* picture);
+
+// Method that returns the current Skia function.
+typedef void (SkiaVersionFunction)(int* major, int* minor, int* patch);
+
+// Called to verify if the Skia versions are compatible.
+typedef bool (AwIsSkiaVersionCompatibleFunction)(SkiaVersionFunction function);
+
 // "vtable" for the functions declared in this file. An instance must be set via
 // AwContents.setAwDrawSWFunctionTable
 struct AwDrawSWFunctionTable {
   AwAccessPixelsFunction* access_pixels;
   AwReleasePixelsFunction* release_pixels;
+  AwCreatePictureFunction* create_picture;
+  AwIsSkiaVersionCompatibleFunction* is_skia_version_compatible;
 };
 
 #endif  // ANDROID_WEBVIEW_PUBLIC_BROWSER_DRAW_SW_H_