This change is fixing "All Java build rules should be loaded from
Starlark" warning flagged by latest buildifier version: [1]. Python
rules are now also loaded from the Starlark.
Also extract codemirror library import to BUILD file. This is needed to
avoid cycle in the workspace file, after importing java rules from
Starlark.
[1] https://github.com/bazelbuild/buildtools/blob/master/WARNINGS.md#native-java
Change-Id: I36192c9465d988b25cf09c250e110f15850910cd
Reformat the Bazel build files with the buildifier tool [1].
The style is different for Bazel files. Most notably, indentation level
is 4 spaces instead of 2, and " is used instead of '.
[1] https://github.com/bazelbuild/buildifier
Change-Id: I95c0c6f11b6d76572797853b4ebb5cee5ebd3c98