Turn on -Wall -Wextra on Mac, and fix all the warnings that crop up for /usr/bin/g++ and Clang 3.3.

src/gpu/GrDrawTargetCaps.h

Index: src/gpu/GrDrawTargetCaps.h
diff --git a/src/gpu/GrDrawTargetCaps.h b/src/gpu/GrDrawTargetCaps.h
index ffacc9e4feb0fa972665a88f2143aeaf3f0b0623..61c9fede08e3500831c7e45230237fa1bf62ece3 100644
--- a/src/gpu/GrDrawTargetCaps.h
+++ b/src/gpu/GrDrawTargetCaps.h
@@ -19,7 +19,7 @@ public:
     SK_DECLARE_INST_COUNT(Caps)
 
     GrDrawTargetCaps() { this->reset(); }
-    GrDrawTargetCaps(const GrDrawTargetCaps& other) { *this = other; }
+    GrDrawTargetCaps(const GrDrawTargetCaps& other) : INHERITED() { *this = other; }
     GrDrawTargetCaps& operator= (const GrDrawTargetCaps&);
 
     virtual void reset();