Use MARISA_DEBUG_IF in scoped-*.h as opposed to MARISA_THROW_IF

These are the only two places that we throw exceptions from header files
in non-debug mode.

With this change, developers can take the marisa library without being
forced to enable exceptions for their whole library / application.

IMO, self-reset does not seem to be fatal enough to throw in production
and MARISA_DEBUG_IF should be enough for us to catch it if we think it
should never happen.

include/marisa/scoped-array.h

@@ -16,7 +16,7 @@ class scoped_array {
   }
 
   void reset(T *array = NULL) {
-    MARISA_THROW_IF((array != NULL) && (array == array_), MARISA_RESET_ERROR);
+    MARISA_DEBUG_IF((array != NULL) && (array == array_), MARISA_RESET_ERROR);
     scoped_array(array).swap(*this);
   }
 

include/marisa/scoped-ptr.h

@@ -16,7 +16,7 @@ class scoped_ptr {
   }
 
   void reset(T *ptr = NULL) {
-    MARISA_THROW_IF((ptr != NULL) && (ptr == ptr_), MARISA_RESET_ERROR);
+    MARISA_DEBUG_IF((ptr != NULL) && (ptr == ptr_), MARISA_RESET_ERROR);
     scoped_ptr(ptr).swap(*this);
   }