Cleanup dump() functions.

We had various variants of defining dump() functions in LLVM. Normalize
them (this should just consistently implement the things discussed in
http://lists.llvm.org/pipermail/cfe-dev/2014-January/034323.html

For reference:
- Public headers should just declare the dump() method but not use
  LLVM_DUMP_METHOD or #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
- The definition of a dump method should look like this:
  #if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
  LLVM_DUMP_METHOD void MyClass::dump() {
    // print stuff to dbgs()...
  }
  #endif

llvm-svn: 293359
diff --git a/llvm/lib/Support/Twine.cpp b/llvm/lib/Support/Twine.cpp
index 465c6e6..d17cd4e 100644
--- a/llvm/lib/Support/Twine.cpp
+++ b/llvm/lib/Support/Twine.cpp
@@ -173,10 +173,12 @@
   OS << ")";
 }
 
+#if !defined(NDEBUG) || defined(LLVM_ENABLE_DUMP)
 LLVM_DUMP_METHOD void Twine::dump() const {
   print(dbgs());
 }
 
-void Twine::dumpRepr() const {
+LLVM_DUMP_METHOD void Twine::dumpRepr() const {
   printRepr(dbgs());
 }
+#endif