[analyzer] Rename functions responsible for CFG-based suppress-on-sink.
[analyzer] Rename functions responsible for CFG-based suppress-on-sink.

Update comments. No functional change intended.

Addresses Devin's post-commit review comments in https://reviews.llvm.org/D35673
and https://reviews.llvm.org/D35674.


git-svn-id: ffe668792ed300d6c2daa1f6eba2e0aa28d7ec6c@310820 91177308-0d34-0410-b5e6-96231b3b80d8

llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,apple/swift-clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,llvm-mirror/clang,apple/swift-clang,llvm-mirror/clang,apple/swift-clang,apple/swift-clang,llvm-mirror/clang,apple/swift-clang