change SkDraw and all Blitters to use pixmap instead of bitmap

src/utils/SkTextureCompressor.h

Index: src/utils/SkTextureCompressor.h
diff --git a/src/utils/SkTextureCompressor.h b/src/utils/SkTextureCompressor.h
index e35bc957ac2c9ee783b30e2caa33070f6077e81a..e31a5ab48d5262168dc0bdf11c400e0a64065167 100644
--- a/src/utils/SkTextureCompressor.h
+++ b/src/utils/SkTextureCompressor.h
@@ -55,10 +55,10 @@ namespace SkTextureCompressor {
     int GetCompressedDataSize(Format fmt, int width, int height);
 
     // Returns an SkData holding a blob of compressed data that corresponds
-    // to the bitmap. If the bitmap colorType cannot be compressed using the 
+    // to the pixmap. If the pixmap colorType cannot be compressed using the 
     // associated format, then we return NULL. The caller is responsible for
     // calling unref() on the returned data.
-    SkData* CompressBitmapToFormat(const SkBitmap& bitmap, Format format);
+    SkData* CompressBitmapToFormat(const SkPixmap&, Format format);
 
     // Compresses the given src data into dst. The src data is assumed to be
     // large enough to hold width*height pixels. The dst data is expected to