Move -verify-pch to use VerifyJobAction

Use the verify hook rather than the compile hook to represent the
-verify-pch action, and move the exising --verify-debug-info action
into its own subclass of VerifyJobAction.  Incidentally change the name
printed by -ccc-print-phases for --verify-debug-info.

llvm-svn: 200938
diff --git a/clang/lib/Driver/ToolChains.cpp b/clang/lib/Driver/ToolChains.cpp
index 9c4213b..d328b16 100644
--- a/clang/lib/Driver/ToolChains.cpp
+++ b/clang/lib/Driver/ToolChains.cpp
@@ -212,7 +212,7 @@
     if (!Dsymutil)
       Dsymutil.reset(new tools::darwin::Dsymutil(*this));
     return Dsymutil.get();
-  case Action::VerifyJobClass:
+  case Action::VerifyDebugInfoJobClass:
     if (!VerifyDebug)
       VerifyDebug.reset(new tools::darwin::VerifyDebug(*this));
     return VerifyDebug.get();