Revert of change SkDraw and all Blitters to use pixmap instead of bitmap (patchset #6 id:100001 of https://codereview.chromium.org/1148793007/)

Reason for revert:
speculative revert to try to unblock DEPS roll

Original issue's description:
> change SkDraw and all Blitters to use pixmap instead of bitmap
>
> BUG=skia:
>
> Committed: https://skia.googlesource.com/skia/+/c31af44336f5eb4a50e83e76e51962d46c3ed458

TBR=scroggo@google.com,jvanverth@google.com,reed@google.com
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Review URL: https://codereview.chromium.org/1164373003
diff --git a/src/utils/SkTextureCompressor.cpp b/src/utils/SkTextureCompressor.cpp
index 9d29d51..12621e1 100644
--- a/src/utils/SkTextureCompressor.cpp
+++ b/src/utils/SkTextureCompressor.cpp
@@ -173,17 +173,19 @@
     return false;
 }
 
-SkData* CompressBitmapToFormat(const SkPixmap& pixmap, Format format) {
-    int compressedDataSize = GetCompressedDataSize(format, pixmap.width(), pixmap.height());
+SkData* CompressBitmapToFormat(const SkBitmap &bitmap, Format format) {
+    SkAutoLockPixels alp(bitmap);
+
+    int compressedDataSize = GetCompressedDataSize(format, bitmap.width(), bitmap.height());
     if (compressedDataSize < 0) {
         return NULL;
     }
 
-    const uint8_t* src = reinterpret_cast<const uint8_t*>(pixmap.addr());
+    const uint8_t* src = reinterpret_cast<const uint8_t*>(bitmap.getPixels());
     SkData* dst = SkData::NewUninitialized(compressedDataSize);
 
-    if (!CompressBufferToFormat((uint8_t*)dst->writable_data(), src, pixmap.colorType(),
-                                pixmap.width(), pixmap.height(), pixmap.rowBytes(), format)) {
+    if (!CompressBufferToFormat((uint8_t*)dst->writable_data(), src, bitmap.colorType(),
+                                bitmap.width(), bitmap.height(), bitmap.rowBytes(), format)) {
         dst->unref();
         dst = NULL;
     }
diff --git a/src/utils/SkTextureCompressor.h b/src/utils/SkTextureCompressor.h
index e31a5ab..e35bc95 100644
--- a/src/utils/SkTextureCompressor.h
+++ b/src/utils/SkTextureCompressor.h
@@ -55,10 +55,10 @@
     int GetCompressedDataSize(Format fmt, int width, int height);
 
     // Returns an SkData holding a blob of compressed data that corresponds
-    // to the pixmap. If the pixmap colorType cannot be compressed using the 
+    // to the bitmap. If the bitmap 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 SkPixmap&, Format format);
+    SkData* CompressBitmapToFormat(const SkBitmap& bitmap, 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
diff --git a/src/utils/SkTextureCompressor_Blitter.h b/src/utils/SkTextureCompressor_Blitter.h
index e522375..73d8ee4 100644
--- a/src/utils/SkTextureCompressor_Blitter.h
+++ b/src/utils/SkTextureCompressor_Blitter.h
@@ -368,7 +368,7 @@
     // If the blitter just sets a single value for each pixel, return the
     // bitmap it draws into, and assign value. If not, return NULL and ignore
     // the value parameter.
-    const SkPixmap* justAnOpaqueColor(uint32_t* value) override {
+    const SkBitmap* justAnOpaqueColor(uint32_t* value) override {
         return NULL;
     }