Revert of change SkDraw and all Blitters to use pixmap instead of bitmap

src/core/SkScan_Path.cpp

Index: src/core/SkScan_Path.cpp
diff --git a/src/core/SkScan_Path.cpp b/src/core/SkScan_Path.cpp
index b7db3b410d603f65c4332450d4d633f543a57f91..9b4b9fd89727e330db13ddf413d00a17e2a74482 100644
--- a/src/core/SkScan_Path.cpp
+++ b/src/core/SkScan_Path.cpp
@@ -344,7 +344,7 @@
     void blitMask(const SkMask&, const SkIRect& clip) override {
         SkDEBUGFAIL("blitMask unexpected");
     }
-    const SkPixmap* justAnOpaqueColor(uint32_t* value) override {
+    const SkBitmap* justAnOpaqueColor(uint32_t* value) override {
         SkDEBUGFAIL("justAnOpaqueColor unexpected");
         return NULL;
     }