clang-cl: Fix remaining bugs in interaction of /Yc and /FI /showIncludes.

Instead of putting the /Yc header into ExtraDeps, give DependencyOutputOptions
a dedicated field for /Yc mode, and let HeaderIncludesCallback hang on to the
full DependencyOutputOptions object, not just ExtraDeps.

Reverts parts of r263352 that are now no longer needed.

llvm-svn: 264182