Bug 697322 - Add easier to use reset method to CallReceiver; r=luke

All users of InvokeArgsGuard that use calleeHasBeenReset use it before
setting a new callee/this in a loop.  We should make it easier to use
by combining the reset with the setup with the setting of the new
callee.

js/src/jsarray.cpp

@@ -2151,8 +2151,7 @@ sort_compare(void *arg, const void *a, const void *b, int *result)
     if (!ag.pushed() && !cx->stack.pushInvokeArgs(cx, 2, &ag))
         return JS_FALSE;
         
-    ag.calleeHasBeenReset();
-    ag.calleev() = ca->fval;
+    ag.setCallee(ca->fval);
     ag.thisv() = UndefinedValue();
     ag[0] = *av;
     ag[1] = *bv;
@@ -3360,8 +3359,7 @@ array_readonlyCommon(JSContext *cx, CallArgs &args)
         if (!kNotPresent) {
             if (!ag.pushed() && !cx->stack.pushInvokeArgs(cx, 3, &ag))
                 return false;
-            ag.calleeHasBeenReset();
-            ag.calleev() = ObjectValue(*callable);
+            ag.setCallee(ObjectValue(*callable));
             ag.thisv() = thisv;
             ag[0] = kValue;
             ag[1] = NumberValue(k);
@@ -3462,8 +3460,7 @@ array_map(JSContext *cx, uintN argc, Value *vp)
         if (!kNotPresent) {
             if (!ag.pushed() && !cx->stack.pushInvokeArgs(cx, 3, &ag))
                 return false;
-            ag.calleeHasBeenReset();
-            ag.calleev() = ObjectValue(*callable);
+            ag.setCallee(ObjectValue(*callable));
             ag.thisv() = thisv;
             ag[0] = kValue;
             ag[1] = NumberValue(k);
@@ -3542,8 +3539,7 @@ array_filter(JSContext *cx, uintN argc, Value *vp)
         if (!kNotPresent) {
             if (!ag.pushed() && !cx->stack.pushInvokeArgs(cx, 3, &ag))
                 return false;
-            ag.calleeHasBeenReset();
-            ag.calleev() = ObjectValue(*callable);
+            ag.setCallee(ObjectValue(*callable));
             ag.thisv() = thisv;
             ag[0] = kValue;
             ag[1] = NumberValue(k);
@@ -3661,8 +3657,7 @@ array_reduceCommon(JSContext *cx, CallArgs &args)
         if (!kNotPresent) {
             if (!ag.pushed() && !cx->stack.pushInvokeArgs(cx, 4, &ag))
                 return false;
-            ag.calleeHasBeenReset();
-            ag.calleev() = ObjectValue(*callable);
+            ag.setCallee(ObjectValue(*callable));
             ag.thisv() = UndefinedValue();
             ag[0] = accumulator;
             ag[1] = kValue;

js/src/jsstr.cpp

@@ -1791,8 +1791,7 @@ FindReplaceLength(JSContext *cx, RegExpStatics *res, ReplaceData &rdata, size_t
         if (!args.pushed() && !cx->stack.pushInvokeArgs(cx, argc, &args))
             return false;
 
-        args.calleeHasBeenReset();
-        args.calleev() = ObjectValue(*lambda);
+        args.setCallee(ObjectValue(*lambda));
         args.thisv() = UndefinedValue();
 
         /* Push $&, $1, $2, ... */

js/src/vm/Stack.h

@@ -208,8 +208,9 @@ class CallReceiver
         return argv_ - 1;
     }
 
-    void calleeHasBeenReset() const {
+    void setCallee(Value calleev) {
         clearUsedRval();
+        this->calleev() = calleev;
     }
 };