Add --src-dir flag to landmines.py.

Add --src-dir flag to landmines.py.

This will make it possible to reuse the script in projects
with different directory layouts than Chromium, since the
current version assumes the root is two levels above the
script location.

BUG=webrtc:5077
TESTED=Manually running the script and running runhooks.

Committed: https://crrev.com/20b291561ce84495d9af94b5cc7f0cb9765d128c
Cr-Commit-Position: refs/heads/master@{#354083}

[kjellander_chromium, 2015-10-14 14:37:26]

kjellander@chromium.org changed reviewers:
+ scottmg@chromium.org

[kjellander_chromium, 2015-10-14 14:41:50]

This will make it possible for WebRTC to reuse the landmines.py script, thus
avoiding to create a copy in our own repo.

Tests performed:

/path/to/chromium $ rm src/.landmines
/path/to/chromium $ src/build/landmines.py --src-dir=foo
Usage: landmines.py [options]

landmines.py: error: Cannot find source root dir at foo

/path/to/chromium $ $ src/build/landmines.py --src-dir=src -v
DEBUG:root:Overriding source root dir. Using: src
gyp_defines -> {}
IsWindows -> False
IsLinux -> True
platform -> 'linux'
builder -> 'ninja'
gyp_generator_flags -> {}

/path/to/chromium $ ls src/.landmines
src/.landmines

/path/to/chromium $ cd src

/path/to/chromium/src $ rm .landmines
/path/to/chromium/src $ build/landmines.py --src-dir=. -v
DEBUG:root:Overriding source root dir. Using: .
gyp_defines -> {}
IsWindows -> False
IsLinux -> True
platform -> 'linux'
builder -> 'ninja'
gyp_generator_flags -> {}

/path/to/chromium/src $ ls .landmines
.landmines

/path/to/chromium/src $ rm .landmines
/path/to/chromium/src $ build/landmines.py -v
gyp_defines -> {}
IsWindows -> False
IsLinux -> True
platform -> 'linux'
builder -> 'ninja'
gyp_generator_flags -> {}

/path/to/chromium/src $ ls .landmines
.landmines

[scottmg, 2015-10-14 17:08:27]

lgtm

[kjellander_chromium, 2015-10-14 18:48:24]

The CQ bit was checked by kjellander@chromium.org to run a CQ dry run

[commit-bot: I haz the power, 2015-10-14 18:49:10]

Dry run: CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1407733002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1407733002/20001

[commit-bot: I haz the power, 2015-10-14 19:00:12]

The CQ bit was unchecked by commit-bot@chromium.org

[commit-bot: I haz the power, 2015-10-14 19:00:12]

Dry run: This issue passed the CQ dry run.

[kjellander_chromium, 2015-10-14 19:23:27]

The CQ bit was checked by kjellander@chromium.org

[commit-bot: I haz the power, 2015-10-14 19:23:37]

CQ is trying da patch. Follow status at
 https://chromium-cq-status.appspot.com/patch-status/1407733002/20001
View timeline at
 https://chromium-cq-status.appspot.com/patch-timeline/1407733002/20001

[commit-bot: I haz the power, 2015-10-14 19:28:18]

Committed patchset #2 (id:20001)

[commit-bot: I haz the power, 2015-10-14 19:30:11]

Patchset 2 (id:??) landed as
https://crrev.com/20b291561ce84495d9af94b5cc7f0cb9765d128c
Cr-Commit-Position: refs/heads/master@{#354083}

[Michael Achenbach, 2015-10-15 07:13:29]

Awesome, now that this is reusable, we should move it into the buildtools repo
for easier sharing with other projects.