Fix "No SCM found for url None" error that can occur after update...

Fix "No SCM found for url None" error that can occur after update

This occurs when gclient compares the cached deps in .gclient_entries
to the new DEPS and tries to construct an SCM for any cached entries
which no longer exist. In this situation gclient doesn't account for
the case where previous entries may have been ignored by setting their
url to None via the custom_deps section in .gclient.

Contributed by Jay Soffian.

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=62540

[jaysoffian, 2010-10-13 21:31:12]

This occurs when gclient compares the cached deps in .gclient_entries
to the new DEPS and tries to construct an SCM for any cached entries
which no longer exist. In this situation gclient doesn't account for
the case where previous entries may have been ignored by setting their
url to None via the custom_deps section in .gclient.

[M-A Ruel, 2010-10-14 01:51:30]

I'll commit tomorrow morning.

http://codereview.chromium.org/3769002/diff/1/2
File gclient.py (right):

http://codereview.chromium.org/3769002/diff/1/2#newcode738
gclient.py:738: if prev_url is None:
I'll change it for "if not prev_url:"