Add CPP_THROW_NEW macro to the build system. This macro should be used when defining a local |operator new| function. It will be set to an empty throw function by default on all platforms except mac CW builds. This will allow us to not crash on systems that expect |operator new| to throw an exception by default and will suppress compiler warnings about how |operator new| should throw an exception instead of returning NULL.

Bug 149032 r=timeless sr=scc

rdf/base/src/nsCompositeDataSource.cpp

@@ -411,7 +411,7 @@ private:
 
     // Hide so that only Create() and Destroy() can be used to
     // allocate and deallocate from the heap
-    static void* operator new(size_t) { return 0; }
+    static void* operator new(size_t) CPP_THROW_NEW { return 0; }
     static void operator delete(void*, size_t) {}
 };
 
@@ -530,7 +530,7 @@ private:
 
     // Hide so that only Create() and Destroy() can be used to
     // allocate and deallocate from the heap
-    static void* operator new(size_t) { return 0; }
+    static void* operator new(size_t) CPP_THROW_NEW { return 0; }
     static void operator delete(void*, size_t) {}
 };