Revert "Use getSize instead of data().size(). NFC."

This reverts commit r283125.

lld needs to be updated.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@283127 91177308-0d34-0410-b5e6-96231b3b80d8

lib/MC/StringTableBuilder.cpp

@@ -34,11 +34,6 @@ StringTableBuilder::StringTableBuilder(Kind K, unsigned Alignment)
   }
 }
 
-size_t StringTableBuilder::getSize() const {
-  assert(isFinalized());
-  return Size;
-}
-
 typedef std::pair<CachedHash<StringRef>, size_t> StringPair;
 
 // Returns the character at Pos from end of a string.