H-BuildIncrement should make use of available type feedback

test/mjsunit/compiler/increment-typefeedback.js

Index: test/mjsunit/compiler/increment-typefeedback.js
diff --git a/test/mjsunit/regress/regress-crbug-173974.js b/test/mjsunit/compiler/increment-typefeedback.js
similarity index 95%
copy from test/mjsunit/regress/regress-crbug-173974.js
copy to test/mjsunit/compiler/increment-typefeedback.js
index 905bd6058a0ad0fe2ebe10e4c7dafbe9945cbe3b..798959296c43014f252d65ae5dd11e00563bfd04 100644
--- a/test/mjsunit/regress/regress-crbug-173974.js
+++ b/test/mjsunit/compiler/increment-typefeedback.js
@@ -27,10 +27,13 @@
 
 // Flags: --allow-natives-syntax
 
-function f() {
-  var count = "";
-  count[0] --;
+function f(x) {
+  x++;
+  return x;
 }
-f();
+
+f(0.5);
+f(0.5);
 %OptimizeFunctionOnNextCall(f);
-f();
+f(0.5);
+assertOptimized(f);