Remove syntaxTree from SourceFileObject
Merge pull request #985 from Microsoft/removeSyntaxTree

Remove syntaxTree from SourceFileObject
Export DisplayPartsSymbolWriter as it is already used in exported types
Update LKG
Remove while true guard
use .pop() on an array instead of setting the length directly.  The latter causes v8 to stop optimizing the method.
Merge pull request #992 from Microsoft/perfWork

use .pop() on an array instead of setting the length directly.  The latt...
Remove nulls from the syntax layer.
Adding support in fidelity for parsing union and parenthesized types
Merge pull request #995 from Microsoft/removeNull

Remove nulls from the syntax layer.
Merge branch 'master' into fidelityParsingUpdates2
Merge pull request #997 from Microsoft/fidelityParsingUpdates2

Adding support in fidelity for parsing union and parenthesized types
Improve walking speed in Fidelity.
Removing commented out code.
Merge pull request #1006 from Microsoft/walkingSpeed

Improve walking speed in Fidelity.
Merge branch 'master' into templates
Addressed CR feedback.