Adds support for detecting modified gyp* files to analyzer

Currently I've special cased gyp* file modifications higher in the
stack. By that I mean if a gyp* file has been modified I don't run
analyze and assume everything has changed. This change adds support
for modification to gyp* files. If a gyp* file has changed it assumes
all targets in the file are modified. Similarly if an included file
has been modified all targets in the file that did the include are
considered modified. Lastly, if one of the modified files is specified
on the command line via -I the I early out and assume everything needs
to be recompiled.

BUG=109173
R=scottmg@chromium.org

Committed: https://code.google.com/p/gyp/source/detail?r=1962

[Mark Mentovai, 2014-08-05 22:09:02]

I’m unable to do any reviews or work for the time being that don’t relate to
crbugs 399276 or 386208/390217. Sorry.

[sky, 2014-08-05 22:31:45]

mark->scottmg

[Mark Mentovai, 2014-08-05 22:34:03]

If scottmg is willing to help, he’d be a suitable reviewer. (He’s also aware of
my current situation.)

[scottmg, 2014-08-05 23:02:43]

LGTM. I wasn't familiar with the analyzer code before, but the description seems
reasonable, and tests seem right to me.

https://codereview.chromium.org/442083004/diff/1/pylib/gyp/generator/analyzer.py
File pylib/gyp/generator/analyzer.py (right):

https://codereview.chromium.org/442083004/diff/1/pylib/gyp/generator/analyzer...
pylib/gyp/generator/analyzer.py:67: def _ToGypPath(path):
I don't understand why some functions are _ and some are __?

https://codereview.chromium.org/442083004/diff/1/pylib/gyp/generator/analyzer...
pylib/gyp/generator/analyzer.py:398: # effected.
nit; affected.

https://codereview.chromium.org/442083004/diff/1/test/analyzer/gyptest-analyz...
File test/analyzer/gyptest-analyzer.new.py (right):

https://codereview.chromium.org/442083004/diff/1/test/analyzer/gyptest-analyz...
test/analyzer/gyptest-analyzer.new.py:52: """Verifies output contains |targets|
and |direct_targets|."""
Looks like there's no |direct_targets| any longer.

[sky, 2014-08-06 00:26:07]

https://codereview.chromium.org/442083004/diff/1/pylib/gyp/generator/analyzer.py
File pylib/gyp/generator/analyzer.py (right):

https://codereview.chromium.org/442083004/diff/1/pylib/gyp/generator/analyzer...
pylib/gyp/generator/analyzer.py:67: def _ToGypPath(path):
On 2014/08/05 23:02:43, scottmg wrote:
> I don't understand why some functions are _ and some are __?

Indeed. Python sites recommend __, which is why I went with that. Then I saw the
Google Python guide which said '_', so I've started doing that. I plan on doing
a cleanup pass and straightening this all out shortly.

https://codereview.chromium.org/442083004/diff/1/pylib/gyp/generator/analyzer...
pylib/gyp/generator/analyzer.py:398: # effected.
On 2014/08/05 23:02:43, scottmg wrote:
> nit; affected.

I ALWAYS get that wrong.

https://codereview.chromium.org/442083004/diff/1/test/analyzer/gyptest-analyz...
File test/analyzer/gyptest-analyzer.new.py (right):

https://codereview.chromium.org/442083004/diff/1/test/analyzer/gyptest-analyz...
test/analyzer/gyptest-analyzer.new.py:52: """Verifies output contains |targets|
and |direct_targets|."""
On 2014/08/05 23:02:43, scottmg wrote:
> Looks like there's no |direct_targets| any longer.

Done.

[sky, 2014-08-06 16:41:15]

Committed patchset #3 manually as r1962 (presubmit successful).