Address two fuzzer bugs

src/core/SkBitmap.cpp

Index: src/core/SkBitmap.cpp
diff --git a/src/core/SkBitmap.cpp b/src/core/SkBitmap.cpp
index 8cb8e4d6fc9f530c290c8fc86477572a6406e592..863169c458b8d76642d3aae13e923c68cb90ede3 100644
--- a/src/core/SkBitmap.cpp
+++ b/src/core/SkBitmap.cpp
@@ -1145,8 +1145,10 @@ bool SkBitmap::ReadRawPixels(SkReadBuffer* buffer, SkBitmap* bitmap) {
     SkImageInfo info;
     info.unflatten(*buffer);
 
-    // If there was an error reading "info", don't use it to compute minRowBytes()
-    if (!buffer->validate(true)) {
+    // If there was an error reading "info" or if it is bogus, 
+    // don't use it to compute minRowBytes()
+    if (!buffer->validate(SkColorTypeValidateAlphaType(info.colorType(),
+                                                       info.alphaType()))) {
         return false;
     }