Fix skydb to work for android

Fix skydb to work for android

I changed skydb start to take a build directory
and read the configuration out of gn args instead
of --release, --debug, etc.  This should be more
flexable and handle all the crazy asan cases
mopy/config.py tries to.  Once we merge sky/tools
into mojo/tools we should make mopy/config use this
method too.

This follows similar patterns to what
mojo/tools/android_mojo_shell.py does, but doesn't
use as much of the (old) android_commands and forwarder
logic.  We could even remove all of that
build/android/pylib code by calling the (new)
adb reverse instead of using Forwarder (in a later patch).

This still only supports a single skydb running
at once, but it should be trivial to move the
skydb.pids file into the build directory or to have
it support more than one instance.  The big question
there is what the command-line usage should look like
when supporting more than one running instance.  See
the mojo-dev thread on the subject.

R=abarth@chromium.org

Committed: https://chromium.googlesource.com/external/mojo/+/dd407ce5866da320896eb88595d66791c2bd498c

[eseidel, 2015-01-09 22:58:50]

https://codereview.chromium.org/816693006/diff/1/sky/tools/debugger/prompt/pr...
File sky/tools/debugger/prompt/prompt.cc (right):

https://codereview.chromium.org/816693006/diff/1/sky/tools/debugger/prompt/pr...
sky/tools/debugger/prompt/prompt.cc:159: uint32_t command_port_;
This was to answer an earlier complaint from jamesr.

https://codereview.chromium.org/816693006/diff/1/sky/tools/skydb
File sky/tools/skydb (left):

https://codereview.chromium.org/816693006/diff/1/sky/tools/skydb#oldcode74
sky/tools/skydb:74: if args.show_command:
I removed support for --show-command.  Sorry Hans. :(

https://codereview.chromium.org/816693006/diff/1/sky/tools/skydb
File sky/tools/skydb (right):

https://codereview.chromium.org/816693006/diff/1/sky/tools/skydb#newcode20
sky/tools/skydb:20: sys.path.insert(0, os.path.join(Paths('ignored').src_root,
'build', 'android'))
As I note in the description, we could *almost* remove this.

[abarth-chromium, 2015-01-09 22:59:19]

lgtm

https://codereview.chromium.org/816693006/diff/1/shell/context.cc
File shell/context.cc (right):

https://codereview.chromium.org/816693006/diff/1/shell/context.cc#newcode83
shell/context.cc:83: ReplaceSubstringsAfterOffset(&handlers_spec, 0, "\\,",
",");
What about \\, ?

[eseidel, 2015-01-09 23:14:05]

On 2015/01/09 22:59:19, abarth wrote:
> lgtm
> 
> https://codereview.chromium.org/816693006/diff/1/shell/context.cc
> File shell/context.cc (right):
> 
> https://codereview.chromium.org/816693006/diff/1/shell/context.cc#newcode83
> shell/context.cc:83: ReplaceSubstringsAfterOffset(&handlers_spec, 0, "\\,",
> ",");
> What about \\, ?

I'm not sure I understand what you're asking?

[abarth-chromium, 2015-01-10 00:05:16]

On 2015/01/09 at 23:14:05, eseidel wrote:
> On 2015/01/09 22:59:19, abarth wrote:
> > lgtm
> > 
> > https://codereview.chromium.org/816693006/diff/1/shell/context.cc
> > File shell/context.cc (right):
> > 
> > https://codereview.chromium.org/816693006/diff/1/shell/context.cc#newcode83
> > shell/context.cc:83: ReplaceSubstringsAfterOffset(&handlers_spec, 0, "\\,",
> > ",");
> > What about \\, ?
> 
> I'm not sure I understand what you're asking?

Consider the following string:

abc\\,def

You'll replace the "\," with ",".  Maybe that's the right thing, but you could
worry that you're supposed to replace the "\\" with "\".  In this case that
comes out the same...  Maybe it always comes out the same?

[eseidel, 2015-01-12 19:16:24]

Committed patchset #1 (id:1) manually as
dd407ce5866da320896eb88595d66791c2bd498c (presubmit successful).