Initial error handling code

src/core/SkBitmap.cpp

Index: src/core/SkBitmap.cpp
diff --git a/src/core/SkBitmap.cpp b/src/core/SkBitmap.cpp
index 63a760c4cf7672a15068f8b801efc7a36d7d530e..13e72c119249c95cad0979c08f1ada59ae05f514 100644
--- a/src/core/SkBitmap.cpp
+++ b/src/core/SkBitmap.cpp
@@ -19,6 +19,7 @@
 #include "SkThread.h"
 #include "SkUnPreMultiply.h"
 #include "SkUtils.h"
+#include "SkValidationUtils.h"
 #include "SkPackBits.h"
 #include <new>
 
@@ -1601,9 +1602,11 @@ void SkBitmap::unflatten(SkFlattenableReadBuffer& buffer) {
     int width = buffer.readInt();
     int height = buffer.readInt();
     int rowBytes = buffer.readInt();
-    int config = buffer.readInt();
+    Config config = (Config)buffer.readInt();
+    buffer.validate((width >= 0) && (height >= 0) && (rowBytes >= 0) &&
+                    SkIsValidConfig(config));
 
-    this->setConfig((Config)config, width, height, rowBytes);
+    this->setConfig(config, width, height, rowBytes);
     this->setIsOpaque(buffer.readBool());
 
     int reftype = buffer.readInt();
@@ -1617,6 +1620,7 @@ void SkBitmap::unflatten(SkFlattenableReadBuffer& buffer) {
         case SERIALIZE_PIXELTYPE_NONE:
             break;
         default:
+            buffer.validate(false);
             SkDEBUGFAIL("unrecognized pixeltype in serialized data");
             sk_throw();
     }