Implement placement operator delete

"If the object is being created as part of a new expression, and an exception
is thrown, the object’s memory is deallocated by calling the appropriate
deallocation function. If the object is being created with a placement new
operator, the corresponding placement delete operator is called—that is, the
delete function that takes the same additional parameters as the placement new
operator. If no matching placement delete is found, no deallocation takes
place."

So to avoid memory leaks, we need to implement placement delete operators that
correspond to our placement new, which we use for leak detection (ironically)
in debug builds.

lib/common/DebugMemLeakFinder.cpp

@@ -754,4 +754,15 @@ void operator delete(void *ptr) throw ()
 	internal_delete(ptr);
 }
 
+void operator delete(void *ptr, const char *file, int line)
+{
+	internal_delete(ptr);
+}
+
+void operator delete[](void *ptr, const char *file, int line)
+{
+	internal_delete(ptr);
+}
+
+
 #endif // BOX_MEMORY_LEAK_TESTING

lib/common/MemLeakFinder.h

@@ -53,6 +53,14 @@ void memleakfinder_notaleak(void *ptr);
 
 void *operator new  (size_t size, const char *file, int line);
 void *operator new[](size_t size, const char *file, int line);
+// "If the object is being created as part of a new expression, and an exception is thrown, the
+// object’s memory is deallocated by calling the appropriate deallocation function. If the object
+// is being created with a placement new operator, the corresponding placement delete operator is
+// called—that is, the delete function that takes the same additional parameters as the placement
+// new operator. If no matching placement delete is found, no deallocation takes place."
+// So to avoid memory leaks, we need to implement placement delete operators too.
+void operator delete  (void *ptr, const char *file, int line);
+void operator delete[](void *ptr, const char *file, int line);
 
 // Define the malloc functions now, if required. These should match the definitions
 // in MemLeakFindOn.h.