add encodeData() to SkImageEncoder, and add encoding to SkImage

src/images/SkImageEncoder.cpp

Index: src/images/SkImageEncoder.cpp
diff --git a/src/images/SkImageEncoder.cpp b/src/images/SkImageEncoder.cpp
index 4b52fcdc8c89708852de7da460510aa904ea4455..5f5ffb82a2901ed16bf28124b2e9af8586d0e02c 100644
--- a/src/images/SkImageEncoder.cpp
+++ b/src/images/SkImageEncoder.cpp
@@ -1,4 +1,3 @@
-
 /*
  * Copyright 2009 The Android Open Source Project
  *
@@ -6,7 +5,6 @@
  * found in the LICENSE file.
  */
 
-
 #include "SkImageEncoder.h"
 #include "SkBitmap.h"
 #include "SkStream.h"
@@ -27,6 +25,15 @@ bool SkImageEncoder::encodeFile(const char file[], const SkBitmap& bm,
     return this->onEncode(&stream, bm, quality);
 }
 
+SkData* SkImageEncoder::encodeData(const SkBitmap& bm, int quality) {
+    SkDynamicMemoryWStream stream;
+    quality = SkMin32(100, SkMax32(0, quality));
+    if (this->onEncode(&stream, bm, quality)) {
+        return stream.copyToData();
+    }
+    return NULL;
+}
+
 bool SkImageEncoder::EncodeFile(const char file[], const SkBitmap& bm, Type t,
                                 int quality) {
     SkAutoTDelete<SkImageEncoder> enc(SkImageEncoder::Create(t));
@@ -34,7 +41,13 @@ bool SkImageEncoder::EncodeFile(const char file[], const SkBitmap& bm, Type t,
 }
 
 bool SkImageEncoder::EncodeStream(SkWStream* stream, const SkBitmap& bm, Type t,
-                                int quality) {
+                                  int quality) {
     SkAutoTDelete<SkImageEncoder> enc(SkImageEncoder::Create(t));
     return enc.get() && enc.get()->encodeStream(stream, bm, quality);
 }
+
+SkData* SkImageEncoder::EncodeData(const SkBitmap& bm, Type t, int quality) {
+    SkAutoTDelete<SkImageEncoder> enc(SkImageEncoder::Create(t));
+    return enc.get() ? enc.get()->encodeData(bm, quality) : NULL;
+}
+