Make HR* macros statements.

Currently HR* macros expand to block expressions which neither need nor
require a closing semicolon. Since at the use site these macros look
like statements which should use a closing semicolon, change the macro
definition to be a statement. This should also fix many warnings around
unneeded semicolons.

Change-Id: I288fdfefa083c6e04a1e7b0a055c8972b7e8b367
Reviewed-on: https://skia-review.googlesource.com/c/189301
Reviewed-by: Brian Salomon <bsalomon@google.com>
Reviewed-by: Mike Klein <mtklein@google.com>
Commit-Queue: Ben Wagner <bungeman@google.com>

src/utils/win/SkHRESULT.h

@@ -22,13 +22,13 @@ void SkTraceHR(const char* file, unsigned long line,
 #define SK_TRACEHR(_hr, _msg) sk_ignore_unused_variable(_hr)
 #endif
 
-#define HR_GENERAL(_ex, _msg, _ret) {\
+#define HR_GENERAL(_ex, _msg, _ret) do {\
     HRESULT _hr = _ex;\
     if (FAILED(_hr)) {\
         SK_TRACEHR(_hr, _msg);\
         return _ret;\
     }\
-}
+} while(false)
 
 //@{
 /**