[PATCH] [MC] Attach labels to existing fragments instead of using a separate fragment

[Eli Bendersky]

LGTM with some nits

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Comment at: lib/MC/MCObjectStreamer.cpp:45
@@ -44,1 +44,3 @@
 
+// If any labels have been emitted but not assigned fragments, ensure that they
+// get assigned, either to F if possible or to a new data fragment.
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This comment probably belongs in the header?

================
Comment at: lib/MC/MCObjectStreamer.cpp:153
@@ +152,3 @@
+  // next fragment.
+  MCDataFragment *F = dyn_cast_or_null<MCDataFragment>(getCurrentFragment());
+  if (F) {
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Can merge the dyn cast into the if here?

http://reviews.llvm.org/D5915