Revert 220853 "Revert 220846 "Make landmines.py take an extra sc..."

Revert 220853 "Revert 220846 "Make landmines.py take an extra sc..."

r220846 was not the root cause of the failure.

> Revert 220846 "Make landmines.py take an extra script via an env..."
> 
> It broke telemetry_unittests.
> http://build.chromium.org/p/chromium.win/builders/Win%207%20Tests%20x64%20%283%29/builds/8782/steps/telemetry_unittests/logs/stdio
> 
> E:\b\depot_tools\python_bin\python_slave.exe src\tools\telemetry\run_tests --browser=release_x64
> No adb found in $PATH, fallback to checked in binary.
> Traceback (most recent call last):
>   File "src\tools\telemetry\run_tests", line 8, in <module>
>     from telemetry.unittest import gtest_testrunner
>   File "E:\b\build\slave\Win_7_Tests_x64__3_\build\src\tools\telemetry\telemetry\__init__.py", line 12, in <module>
>     from telemetry.core.browser_options import BrowserFinderOptions
>   File "E:\b\build\slave\Win_7_Tests_x64__3_\build\src\tools\telemetry\telemetry\core\browser_options.py", line 12, in <module>
>     from telemetry.core import browser_finder
>   File "E:\b\build\slave\Win_7_Tests_x64__3_\build\src\tools\telemetry\telemetry\core\browser_finder.py", line 9, in <module>
>     from telemetry.core.backends.chrome import android_browser_finder
>   File "E:\b\build\slave\Win_7_Tests_x64__3_\build\src\tools\telemetry\telemetry\core\backends\chrome\android_browser_finder.py", line 17, in <module>
>     from telemetry.core.backends.chrome import android_browser_backend
>   File "E:\b\build\slave\Win_7_Tests_x64__3_\build\src\tools\telemetry\telemetry\core\backends\chrome\android_browser_backend.py", line 15, in <module>
>     from telemetry.core.backends.chrome import chrome_browser_backend
>   File "E:\b\build\slave\Win_7_Tests_x64__3_\build\src\tools\telemetry\telemetry\core\backends\chrome\chrome_browser_backend.py", line 19, in <module>
>     from telemetry.core.backends.chrome import extension_dict_backend
>   File "E:\b\build\slave\Win_7_Tests_x64__3_\build\src\tools\telemetry\telemetry\core\backends\chrome\extension_dict_backend.py", line 9, in <module>
>     from telemetry.core.backends.chrome import inspector_backend
>   File "E:\b\build\slave\Win_7_Tests_x64__3_\build\src\tools\telemetry\telemetry\core\backends\chrome\inspector_backend.py", line 19, in <module>
>     from telemetry.core.jsheap import model
> ImportError: No module named jsheap
> 
> > Make landmines.py take an extra script via an env var.
> > 
> > The extra Python script to run can be specified via env var
> > EXTRA_LANDMINES_SCRIPT.
> > 
> > BUG=223636
> > 
> > Review URL: https://chromiumcodereview.appspot.com/23604016
> 
> TBR=sivachandra@chromium.org
> 
> Review URL: https://codereview.chromium.org/23533016

TBR=tkent@chromium.org

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=220870

[tkent, 2013-09-02 21:51:21]

Committed patchset #1 manually as r220870.

[tkent, 2013-09-02 21:58:54]

I reverted the revert.  Sorry for the trouble.