Add TestRules for content shell test and refactor test bases

Similar to crrev/2632043002/, this CL create TestRule for each existing test base
class (ContentDetectionTestBase, JavaBridgeTestBase, NativeLibraryTestBase).
It refactors these test base classes and new TestRules on top of test common layer.
It also remove any inheritance field reference for mTestCallbackHelperContainer to
calling the new API getTestCallbackHelperContainer() for the purpose of common
implementation.

BUG=640116

Review-Url: https://codereview.chromium.org/2739603003
Cr-Original-Commit-Position: refs/heads/master@{#455755}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: a4394cde973e9e7e564185b560a229ba8f59889d
1 file changed