Implement web app definition parsing.

chrome/test/data/web_app_info/full.json

Index: chrome/test/data/web_app_info/full.json
diff --git a/chrome/test/data/web_app_info/full.json b/chrome/test/data/web_app_info/full.json
new file mode 100644
index 0000000000000000000000000000000000000000..d46b7a2350c020d6198a6add44e3ac3099959128
--- /dev/null
+++ b/chrome/test/data/web_app_info/full.json
@@ -0,0 +1,14 @@
+{
+  "name": "hello",
+  "description": "This app is super awesome",
+  "launch_url": "launch_url",
+  "launch_container": "panel",
+  "privileges": [ "geolocation", "notifications" ],
+  "urls": [ "foobar", "baz" ],
+  "icons": {
+    "ignored": "ignored.png",
+    "16": "16.png",
+    // We also ignore this because it is larger than 128.

[Erik does not do reviews, 2010/11/15 19:45:36]

I thought our JSON parser barfed on comments

[Aaron Boodman, 2010/11/16 03:44:45]

The one in v8 does (as per the spec), but the one that we wrote (in base/json)
accepts them, which I think is quite nice.

[Erik does not do reviews, 2010/11/16 23:43:02]

agree.  that always bugged me about the JSON spec.

+    "500": "500.png"
+  }
+}