[turbofan] Clean up and factor out branch generation logic.

src/compiler/ia32/instruction-selector-ia32.cc

Index: src/compiler/ia32/instruction-selector-ia32.cc
diff --git a/src/compiler/ia32/instruction-selector-ia32.cc b/src/compiler/ia32/instruction-selector-ia32.cc
index c242fb431c6f343d99875aea584b7372ffa482c9..72ef4ab0f8c5c1dd0833a4c43d25de14dda50e27 100644
--- a/src/compiler/ia32/instruction-selector-ia32.cc
+++ b/src/compiler/ia32/instruction-selector-ia32.cc
@@ -1010,10 +1010,6 @@ void VisitWordCompareZero(InstructionSelector* selector, Node* user,
 void InstructionSelector::VisitBranch(Node* branch, BasicBlock* tbranch,
                                       BasicBlock* fbranch) {
   FlagsContinuation cont(kNotEqual, tbranch, fbranch);
-  if (IsNextInAssemblyOrder(tbranch)) {  // We can fallthru to the true block.
-    cont.Negate();
-    cont.SwapBlocks();
-  }
   VisitWordCompareZero(this, branch, branch->InputAt(0), &cont);
 }