[tests] Remove space between '%' and runtime function names in mjsunit

TBR=ishell@chromium.org

Bug: v8:6457
Change-Id: I09d7d6ff8460688b7ddf25f733aea73a620db953
Reviewed-on: https://chromium-review.googlesource.com/523037Reviewed-by: Adam Klein <adamk@chromium.org>
Commit-Queue: Adam Klein <adamk@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45699}

test/mjsunit/regress/regress-5902.js

@@ -19,7 +19,7 @@ Object.getOwnPropertyNames(global).forEach(function(name) {
   var obj = global[name];
 
   // Skip non-receivers.
-  if (! % IsJSReceiver(obj)) return;
+  if (!%IsJSReceiver(obj)) return;
 
   // Skip non-natives.
   if (!obj.toString().includes('native')) return;

test/mjsunit/wasm/js-api.js

@@ -8,11 +8,11 @@ load('test/mjsunit/wasm/wasm-constants.js');
 load('test/mjsunit/wasm/wasm-module-builder.js');
 
 function unexpectedSuccess() {
-  % AbortJS('unexpected success');
+  %AbortJS('unexpected success');
 }
 
 function unexpectedFail(error) {
-  % AbortJS('unexpected fail: ' + error);
+  %AbortJS('unexpected fail: ' + error);
 }
 
 function assertEq(val, expected) {