Checking structure sizes before reading them from memory to avoid overflowing the buffer's stream.

include/core/SkRegion.h

Index: include/core/SkRegion.h
diff --git a/include/core/SkRegion.h b/include/core/SkRegion.h
index a088d546200be5211aff976fddc2118a1b392af1..a21afb2d9b298fe39525b2b9fcdb780156030e16 100644
--- a/include/core/SkRegion.h
+++ b/include/core/SkRegion.h
@@ -361,13 +361,15 @@ public:
      *  Write the region to the buffer, and return the number of bytes written.
      *  If buffer is NULL, it still returns the number of bytes.
      */
-    uint32_t writeToMemory(void* buffer) const;
-
+    size_t writeToMemory(void* buffer) const;
     /**
-     *  Initialized the region from the buffer, returning the number
-     *  of bytes actually read.
+     * Initializes the region from the buffer
+     *
+     * @param buffer Memory to read from
+     * @param length Amount of memory available in the buffer
+     * @return number of bytes read or 0 if there was not enough memory available
      */
-    uint32_t readFromMemory(const void* buffer);
+    size_t readFromMemory(const void* buffer, size_t length);
 
     /**
      *  Returns a reference to a global empty region. Just a convenience for