When indexing an empty Swift file, we get a unit file that doesn’t have any record dependency declared on the source file. Because of this, we always assume that the empty file has an out of date index store entry and re-index it on project open. Write empty record files to fix this.
rdar://128711594
For various reasons, it can be useful/interesting to create builds of
Swift that minimize dependencies. Let's try to keep that working as long
as we can.
This makes the tests more focused on what they are interested in testing
and allows flexibility on changing dependency printing on the clang side
without breaking the swift tests.
This converts the instances of the pattern for which we have a proper
substitution in lit. This will make it easier to replace it
appropriately with Windows equivalents.
