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

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

Index: src/compiler/arm/instruction-selector-arm.cc
diff --git a/src/compiler/arm/instruction-selector-arm.cc b/src/compiler/arm/instruction-selector-arm.cc
index 146aede53dc6e5ada6ff5bd5baa29e253e37995d..6e1e0846da4217fa7ef90aa990fa4d2a75aca47a 100644
--- a/src/compiler/arm/instruction-selector-arm.cc
+++ b/src/compiler/arm/instruction-selector-arm.cc
@@ -1170,10 +1170,6 @@ 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);
 }