gn desc: printing public_deps without --all and --tree

tools/gn/command_desc.cc

Index: tools/gn/command_desc.cc
diff --git a/tools/gn/command_desc.cc b/tools/gn/command_desc.cc
index 8dbe6de7de932ec9b67c7cf2219cc6acbf6b8293..58c835320d1020171c6009df70cefedfba00de7b 100644
--- a/tools/gn/command_desc.cc
+++ b/tools/gn/command_desc.cc
@@ -372,8 +372,14 @@ Printing outputs
 
 Printing deps
 
-  Deps will include all public, private, and data deps (TODO this could be
-  clarified and enhanced) sorted in order applying. The following may be used:
+  Deps could include public, private and data deps.
+
+  If the command is invoked with --tree or --all, deps will include all public,

[brettw, 2017/05/23 17:23:05]

Documentation formatting: Can you wrap this together in one paragraph. Separate
paragraphs should be separated by blank lines (as opposed to newlines but no
blank like you did).

[mbonadei1, 2017/05/26 09:29:44]

Done.

+  private and data deps.
+  If the command is invoked without --tree and --all deps will only include
+  private and data deps. In this case public deps will be printed as part of

[brettw, 2017/05/23 17:23:05]

This says "deps" will include data deps, is that right? If this is right, can we
change it? Data deps are very different and aren't linked. It doesn't make sense
to include this but not public_deps.

Can we separate out data_deps as well like you did for public and private?

[mbonadei1, 2017/05/26 09:29:44]

I am not sure I am following, let me try to rephrase to be sure we
are on the same page.

If we are splitting private and public deps it does not make sense
to include data_deps in the private deps (this change will be done
in the function Target::GetDeps).

After this change we can also add another field to the target
description, this field will be called data_deps and it will always
include data deps. Is this right?

+  the section "public_deps".
+  Deps will be sorted in order applying. The following may be used:
 
   --all
       Collects all recursive dependencies and prints a sorted flat list. Also