Add support for logging information about mojo messages retrieved by the mojo debugger
from the message pipes.

This includes the following:-
1. Number of bytes in the message.
2. Number of fields in the message.
3. The message id.
4. The request id of the message.
5. Whether the message expects a response message.
6. Whether the message is a response message.
7. The URL of the service.

We also intercept the first message pipe which is used for
vending services in the debugger.

Support for tracing additional information will be added as needed.

BUG=360188
TBR=viettrungluu

Review URL: https://codereview.chromium.org/354043003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@282417 0039d316-1c4b-4281-b951-d872f2087c98
diff --git a/mojo/mojo.gyp b/mojo/mojo.gyp
index 0593bcf..1aa4e8c 100644
--- a/mojo/mojo.gyp
+++ b/mojo/mojo.gyp
@@ -514,6 +514,7 @@
       'includes': [ 'public/tools/bindings/mojom_bindings_generator.gypi' ],
       'sources': [
         'spy/public/spy.mojom',
+        'spy/common.h',
         'spy/spy.cc',
         'spy/spy.h',
         'spy/spy_server_impl.h',