Add new apis for view state migration and convert the remaining old preferences to the new apis.
Fix the hang issue when viewing a search result with state.json file open.
Implement view states migration from the old preference model.
Merge remote-tracking branch 'origin' into rlim/view-state-migration

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Add deprecation warnings for the old APIs.
Fix all broken integration tests with one exception -- excluding one failing test in WorkingSetView tests.
Add xit to fix JSLint error.
Store working set files in a project layer.
Store project tree states in the project layer.
Making changes to review feedbacks.
Use the project layer in the right way.
Merge remote-tracking branch 'origin' into rlim/view-state-migration

Conflicts:
	src/preferences/PreferencesManager.js
JSDoc for project layer object and implement new deprecation warning function.
Remove "Error" messge from the stack.
Concatenate call stack to deprecation message and show it as one warning.
Update copyright year to 2014 and remove jslint comment.
Add "console" to globals directive since we don't set "devel" option in jslint directive any more.
Fixes nits (including deprecation warning showing proper client ID)
Merge pull request #6740 from adobe/rlim/view-state-migration

Preferences / view state migration