Fix leak in BlurTest

tests/BlurTest.cpp

Index: tests/BlurTest.cpp
===================================================================
--- tests/BlurTest.cpp	(revision 11722)
+++ tests/BlurTest.cpp	(working copy)
@@ -183,6 +183,9 @@
     for ( ; i < resultCount; ++i) {
         result[i] = 0;
     }
+
+    SkMask::FreeImage(src.fImage);
+    SkMask::FreeImage(dst.fImage);
 }
 
 // Implement a step function that is 255 between min and max; 0 elsewhere.