more powerful copies command

[GoogleCodeExporter]

For building webkit/glue in an upstream checkout, we need the WebKit api 
headers to be in third_party/WebKit/WebKit/chromium.  These headers are 
in a different part of the tree, so for now, I'm just copying the headers to 
the desired path.  See change here:

http://codereview.chromium.org/1266001

Some problems with the approach:
- copies isn't recursive, so I have to specify each directory.  adding a new 
subdirectory will require a 2 sided change.  It would be nice if there was a 
recursive version of copies
- it would be nice if I could make symlinks or hardlinks (ntfs supports 
hardlines for files, but not directories).  This makes it less likely that 
people 
will edit the wrong header.  If the hardlink fails, falling back to a copy 
sounds fine.

Original issue reported on code.google.com by tony@chromium.org on 25 Mar 2010 at 2:10

[GoogleCodeExporter]

FYI, we should support recursive copies on Windows since r801. Have you tried 
again 
recently?

Original comment by mmoss@chromium.org on 3 May 2010 at 8:00

[GoogleCodeExporter]

I haven't tried with a r801 or newer.  I can't access my windows computer right 
now so I can't check (if you want 
to debug why I can ping, but not rdp to my windows box at my desk, I would be 
forever grateful).

Original comment by tony@chromium.org on 6 May 2010 at 9:18

[GoogleCodeExporter]

The recursive copying seems to work for me!  Thanks!  There does however seem 
to be a bug where the copy command seems to run on every build (i.e., the 
dependencies are wrong).

Original comment by tony@chromium.org on 14 Jul 2010 at 11:50