Expose an API to get a bitmap's size in bytes.

Change-Id: I960c3b02b1ba8d3a8d92aaa98955a159e6f3a228
http://b/3184897

api/current.xml

@@ -76371,6 +76371,17 @@
 <parameter name="offsetXY" type="int[]">
 </parameter>
 </method>
+<method name="getByteCount"
+ return="int"
+ abstract="false"
+ native="false"
+ synchronized="false"
+ static="false"
+ final="true"
+ deprecated="not deprecated"
+ visibility="public"
+>
+</method>
 <method name="getConfig"
  return="android.graphics.Bitmap.Config"
  abstract="false"

graphics/java/android/graphics/Bitmap.java

@@ -19,7 +19,6 @@ package android.graphics;
 import android.os.Parcel;
 import android.os.Parcelable;
 import android.util.DisplayMetrics;
-
 import java.io.OutputStream;
 import java.nio.Buffer;
 import java.nio.ByteBuffer;
@@ -342,7 +341,7 @@ public final class Bitmap implements Parcelable {
         }
 
         long bufferSize = (long)elements << shift;
-        long pixelSize = (long)getRowBytes() * getHeight();
+        long pixelSize = getByteCount();
 
         if (bufferSize < pixelSize) {
             throw new RuntimeException("Buffer not large enough for pixels");
@@ -378,7 +377,7 @@ public final class Bitmap implements Parcelable {
         }
 
         long bufferBytes = (long)elements << shift;
-        long bitmapBytes = (long)getRowBytes() * getHeight();
+        long bitmapBytes = getByteCount();
 
         if (bufferBytes < bitmapBytes) {
             throw new RuntimeException("Buffer not large enough for pixels");
@@ -821,6 +820,14 @@ public final class Bitmap implements Parcelable {
         return nativeRowBytes(mNativeBitmap);
     }
 
+    /**
+     * Returns the number of bytes used to store this bitmap's pixels.
+     */
+    public final int getByteCount() {
+        // int result permits bitmaps up to 46,340 x 46,340
+        return getRowBytes() * getHeight();
+    }
+
     /**
      * If the bitmap's internal config is in one of the public formats, return
      * that config, otherwise return null.

graphics/tests/graphicstests/src/android/graphics/BitmapTest.java

@@ -16,8 +16,6 @@
 
 package android.graphics;
 
-import android.graphics.Bitmap;
-import android.graphics.Color;
 import android.test.suitebuilder.annotation.SmallTest;
 import junit.framework.TestCase;
 
@@ -42,6 +40,10 @@ public class BitmapTest extends TestCase {
         assertEquals("rowbytes", 200, bm2.getRowBytes());
         assertEquals("rowbytes", 200, bm3.getRowBytes());
         
+        assertEquals("byteCount", 80000, bm1.getByteCount());
+        assertEquals("byteCount", 40000, bm2.getByteCount());
+        assertEquals("byteCount", 40000, bm3.getByteCount());
+
         assertEquals("height", 200, bm1.getHeight());
         assertEquals("height", 200, bm2.getHeight());
         assertEquals("height", 200, bm3.getHeight());