[protoc_wrapper] RuntimeException -> RuntimeError

The former type is not defined.

Change-Id: Ia92aeb231105a653c731247675462068aa3aca5a
Reviewed-on: https://fuchsia-review.googlesource.com/c/third_party/protobuf/+/442718
Reviewed-by: Oliver Newman <olivernewman@google.com>
diff --git a/protoc_wrapper.py b/protoc_wrapper.py
index 56e14e7..ccba5f0 100755
--- a/protoc_wrapper.py
+++ b/protoc_wrapper.py
@@ -51,7 +51,7 @@
         contents.append(stripped_line)
         if stripped_line == PROTOC_INCLUDE_POINT:
           if include_point_found:
-            raise RuntimeException("Multiple include points found.")
+            raise RuntimeError("Multiple include points found.")
           include_point_found = True
           extra_statement = "#include \"{0}\"".format(include)
           contents.append(extra_statement)