Fix checked mode error

Fix checked mode error

R=jmesserly@google.com

Committed: https://github.com/dart-lang/dev_compiler/commit/7c8ca4ce4038ca0e1754fd42bf16f1af32d24903

[vsm, 2015-05-29 19:22:06]

vsm@google.com changed reviewers:
+ jmesserly@google.com

[vsm, 2015-05-29 19:22:13]

https://codereview.chromium.org/1167543002/diff/1/lib/src/dependency_graph.dart
File lib/src/dependency_graph.dart (right):

https://codereview.chromium.org/1167543002/diff/1/lib/src/dependency_graph.da...
lib/src/dependency_graph.dart:204:
newResources.add(graph.nodeFromUri(uri.resolve(resource)));
This was breaking on checked mode in angular todo, where one of the "resources"
was an html file - HtmlSourceNode.

[vsm, 2015-05-29 19:29:56]

Filter out empty string

[vsm, 2015-05-29 19:32:32]

One more related bug

https://codereview.chromium.org/1167543002/diff/20001/lib/src/options.dart
File lib/src/options.dart (right):

https://codereview.chromium.org/1167543002/diff/20001/lib/src/options.dart#ne...
lib/src/options.dart:317: .toList(),
Before, we had [''] - which caused one bogus resource load.

[Jennifer Messerly, 2015-05-29 19:57:01]

lgtm

[vsm, 2015-05-29 20:18:08]

Committed patchset #2 (id:20001) manually as
7c8ca4ce4038ca0e1754fd42bf16f1af32d24903 (presubmit successful).