eliminate the std::ostream form of WriteAsOperand and update clients.
This also updates dominator related stuff.

llvm-svn: 79825
diff --git a/llvm/lib/CodeGen/MachineDominators.cpp b/llvm/lib/CodeGen/MachineDominators.cpp
index 37c8601..78de02a 100644
--- a/llvm/lib/CodeGen/MachineDominators.cpp
+++ b/llvm/lib/CodeGen/MachineDominators.cpp
@@ -51,3 +51,8 @@
 void MachineDominatorTree::releaseMemory() {
   DT->releaseMemory();
 }
+
+void MachineDominatorTree::print(std::ostream &OS, const Module*) const {
+  raw_os_ostream OSS(OS);
+  DT->print(OSS);
+}