[PATCH] Fix regression introduced in r205566.

[Simon Atanasyan]

LGTM with some minor notes.

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Comment at: include/lld/Driver/GnuLdInputGraph.h:81
@@ -80,3 +80,3 @@
   /// to start processing files as part of the input element from beginning.
   /// Reset the next file index to 0 only if the node is an archive library.
   void resetNextIndex() override {
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This phrase //only if the node is an archive library// does not correspond to the current code. Now we reset the next file index for shared libraries too.

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Comment at: lib/Core/Resolver.cpp:65
@@ -67,2 +64,3 @@
   // --start-group/--end-group.
-  _context.getInputGraph().notifyProgress();
+  llvm::dbgs() << "undefAdded: " << undefAdded << "\n";
+  if (undefAdded) {
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It is not good to always print //undefAdded: ...// in debug mode. Let's remove this debug output or surround it by the `DEBUG_WITH_TYPE` macros.

================
Comment at: lib/Core/Resolver.cpp:182
@@ -180,2 +181,3 @@
 
-// called on each atom when a file is added
+// Called on each atom when a file is added. Returns true if a given
+// atom is added to the symbol table.
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The comment //Returns true// is inconsistent. The `Resolver::doDefinedAtom()` method has `void` return type.

http://reviews.llvm.org/D3734