Code: Analysis fixes.
Margin: Removes unnecessary array declaration.
Margin: Rescues TextView property from throwing.
TransientIO: Catch exception after retrying.
Fixes #1040.
SourceMap: Source-map processing disableable.
Fixes #1046.
Compiler: Skip when preview is diabled. (#1046)
Merge pull request #1039 from am11/master

Miscellaneous fixes