Fix typos in the generate_stubs code

Change-Id: Ibe06fb644a8ffb3cb83701b9faa55b3ade79a20d
Reviewed-on: https://chromium-review.googlesource.com/c/1316771Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Commit-Queue: Dirk Pranke <dpranke@chromium.org>
Cr-Commit-Position: refs/heads/master@{#605393}

tools/generate_stubs/generate_stubs_unittest.py

@@ -6,7 +6,7 @@
 """Unittest for the generate_stubs.py.
 
 Since generate_stubs.py is a code generator, it is hard to do a very good
-test.  Instead of creating a golden-file test, which might be flakey, this
+test.  Instead of creating a golden-file test, which might be flaky, this
 test elects instead to verify that various components "exist" within the
 generated file as a sanity check.  In particular, there is a simple hit
 test to make sure that umbrella functions, etc., do try and include every