__except () is the canonical layout for code that uses __try/__except,
Microsoft's structured exception handling. The majority of __except
uses in our code use a space after the keyword. However cpplint.py
thinks that __except is a function name. Apparently we have been forcing
this through by ignoring the presubmits. This just adds __except to the
list of exceptions to the whitespace/parens rule.

Change-Id: I2384cd32f26e3aa6a4b0150451a9a61147483e2d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/2173644
Commit-Queue: Aaron Gable <agable@chromium.org>
Auto-Submit: Bruce Dawson <brucedawson@chromium.org>
Reviewed-by: Aaron Gable <agable@chromium.org>