[mlir] RewriterBase::mergeBlocks: Replace uses with rewriter

[springerm]

Summary

This is to make sure that listeners (such as the GreedyPatternRewriteDriver) will be notified that users of the block arguments have been modified.

[springerm]

Moved into D144549.

mlir/lib/IR/PatternMatch.cpp

void RewriterBase::mergeBlocks(Block *source, Block *dest,
   assert(llvm::all_of(source->getPredecessors(),
                       [dest](Block *succ) { return succ == dest; }) &&
          "expected 'source' to have no predecessors or only 'dest'");
   assert(argValues.size() == source->getNumArguments() &&
          "incorrect # of argument replacement values");
 
   // Replace all of the successor arguments with the provided values.
   for (auto it : llvm::zip(source->getArguments(), argValues))
-    std::get<0>(it).replaceAllUsesWith(std::get<1>(it));
+    replaceAllUsesWith(std::get<0>(it), std::get<1>(it));
 
   // Splice the operations of the 'source' block into the 'dest' block and erase
   // it.
   dest->getOperations().splice(dest->end(), source->getOperations());
   source->dropAllUses();
   source->erase();
 }