Dart: Allows the mojom package's generate script to download .mojoms.

Dart: Allows the mojom package's generate script to download .mojoms.

This change adds an option to generate.dart that causes it to look for
files named '.mojoms' in a package. That file contains https:// URLs
for .mojom files. The generate.dart script downloads the files and
invokes Mojo's bindings generation on them.

This change also fixes a but in Dart bindings generation, which
caused a failure when generating only bindings for Dart.

BUG=
R=johnmccutchan@google.com

Committed: https://chromium.googlesource.com/external/mojo/+/f92948b9155cb3429e69b12fdecbe479aa79bc7a

[zra, 2015-07-03 21:08:34]

zra@google.com changed reviewers:
+ johnmccutchan@google.com

[zra, 2015-07-03 21:08:35]

I'll be out for the next two weeks, so not urgent. Also feel free to take this
CL over if it's needed before I'm back on July 20th.

Cheers,
Zach

[Cutch, 2015-07-20 15:39:09]

https://codereview.chromium.org/1210253006/diff/100001/mojo/dart/mojom/lib/ge...
File mojo/dart/mojom/lib/generate.dart (right):

https://codereview.chromium.org/1210253006/diff/100001/mojo/dart/mojom/lib/ge...
mojo/dart/mojom/lib/generate.dart:102: /// mojom direcoty with the downloaded
mojoms, creating the directory if needed.
direcoty -> directory

https://codereview.chromium.org/1210253006/diff/100001/mojo/dart/mojom/lib/ge...
mojo/dart/mojom/lib/generate.dart:105: /// root: https://www.example.com/mojoms
Why use a stateful format over a list of uris?

https://codereview.chromium.org/1210253006/diff/100001/mojo/dart/mojom/lib/ge...
mojo/dart/mojom/lib/generate.dart:126: if (line.isEmpty || line.startsWith('#'))
continue;
strip leading whitespace?

https://codereview.chromium.org/1210253006/diff/100001/mojo/dart/mojom/lib/ge...
mojo/dart/mojom/lib/generate.dart:139: if (!repoRoot.startsWith('https://')) {
What if I want to use http?

[zra, 2015-07-20 21:09:05]

https://codereview.chromium.org/1210253006/diff/100001/mojo/dart/mojom/lib/ge...
File mojo/dart/mojom/lib/generate.dart (right):

https://codereview.chromium.org/1210253006/diff/100001/mojo/dart/mojom/lib/ge...
mojo/dart/mojom/lib/generate.dart:102: /// mojom direcoty with the downloaded
mojoms, creating the directory if needed.
On 2015/07/20 15:39:09, Cutch wrote:
> direcoty -> directory

Done.

https://codereview.chromium.org/1210253006/diff/100001/mojo/dart/mojom/lib/ge...
mojo/dart/mojom/lib/generate.dart:105: /// root: https://www.example.com/mojoms
On 2015/07/20 15:39:08, Cutch wrote:
> Why use a stateful format over a list of uris?

Related mojoms can import each other. The convention appears to be that import
paths are relative to some root directory. The root for imports could be at any
point in a URI. This format is stateful so we can know where the root is, and
recreate the host's tree in such a way that the import root is in a known place.
That is, it will always be the [mojomsDir] directory created below.

https://codereview.chromium.org/1210253006/diff/100001/mojo/dart/mojom/lib/ge...
mojo/dart/mojom/lib/generate.dart:126: if (line.isEmpty || line.startsWith('#'))
continue;
On 2015/07/20 15:39:08, Cutch wrote:
> strip leading whitespace?

Done.

https://codereview.chromium.org/1210253006/diff/100001/mojo/dart/mojom/lib/ge...
mojo/dart/mojom/lib/generate.dart:139: if (!repoRoot.startsWith('https://')) {
On 2015/07/20 15:39:08, Cutch wrote:
> What if I want to use http?

Removed restriction as discussed.

[Cutch, 2015-07-20 21:11:53]

lgtm

[zra, 2015-07-20 22:43:34]

Committed patchset #7 (id:120001) manually as
f92948b9155cb3429e69b12fdecbe479aa79bc7a (presubmit successful).