Fix missing mandoline deps.

mandoline/app/BUILD.gn

Index: mandoline/app/BUILD.gn
diff --git a/mandoline/app/BUILD.gn b/mandoline/app/BUILD.gn
index bbf483dd41b5e7a1d013cf71872406c46816633a..e74aeb1f76f13a9ca5edf0281c85afed75a2c67d 100644
--- a/mandoline/app/BUILD.gn
+++ b/mandoline/app/BUILD.gn
@@ -16,7 +16,6 @@ group("app") {
   }
 
   data_deps = [
-    "//components/html_viewer",

[msw, 2015/05/15 16:53:10]

Why does moving this to mandoline/app/desktop help?
If we need html_viewer for android and desktop, isn't this right?

[jam, 2015/05/18 14:21:51]

the issue is that one when builds "mandoline", that builds the
mandoline/mandoline_apk targets in mandoline/app/{android,desktop}. the android
apk depended on html_viewer already. the desktop executable target didn't. they
don't depend on mandoline/app group.

[msw, 2015/05/18 18:04:42]

Ah ok, then shouldn't we move these other data deps to the mandoline targets as
well? Building "mandoline" from a clean output dir should suffice. I think it'd
be nice if this "app" target itself were renamed to be a cross-platform
"mandoline" target, listing the shared desktop/android deps and the
platform-specific executable target.

[jam, 2015/05/20 15:45:28]

I don't know why exactly this app group was added. we should figure that out
asynchronously, but it seems we should land this now because we need building
"mandoline" to work correctly.

i can verify that building mandoline alone with this change fixes things.

     "//mandoline/ui/browser",
     "//mandoline/services/core_services",
     "//mojo/runner:mojo_runner",