[PATCH] Include non-explicit submodules in exported module list

[Richard Smith]

  This looks correct to me.

  Since we're including non-explicit submodules in the result of `getExportedModules`, please update `ASTReader::makeModuleVisible` to remove the code that handles them there.

  Alternatively, you could add a loop to `Module::isModuleVisible` to check whether the parent is visible for a non-`explicit` module; this would make the `VisibleModulesCache` smaller.

http://llvm-reviews.chandlerc.com/D2100