Add more tests to SDK Manager.

Slightly change DownloadCache and SettingsController
and provide unit tests for these.

Change-Id: Id5045f7725c870cc3c117c0269aaf080570dd7b4
adding back iml file
Merge "Add more tests to SDK Manager." into idea133
Fix LintDriver's ClassEntry compareTo method to handle duplicate paths

Without this fix, sorting ClassEntry objects could throw a
  Comparison method violates its general contract!
error if there were duplicates on the list.

This might be the cause of
67827: Gradle Build Fails with Lint Comparison Failure
(unless there is some other scenario that the comparator is also broken
for)

Change-Id: Ic75b909040fad541f17cadbb1664569b9742ccc2
Merge "Fix LintDriver's ClassEntry compareTo method to handle duplicate paths" into idea133
Fix formatting of markup strings

If there are spaces between elements we need to preserve that.

Change-Id: I0b0a63dbc40d34aa61cb774d7167dbe660e7977c
Merge "Fix formatting of markup strings" into idea133
Prevent whitespaces in string res during merger.

Change-Id: I4a93839edf4320f1d1482b465f8fdeea96ed02aa
Merge "Prevent whitespaces in string res during merger." into idea133
Merge remote-tracking branch 'aosp/idea133' into instrumentation_runner_options
will have to clean up the iml files at some point