Remove old tests that have been migrated to the v8 repo.

LayoutTests/fast/js/script-tests/excessive-comma-usage.js

-description("Test that we can handle excessively large initializer lists");
-
-var initializerTestString = "var a=0";
-for (var i = 0; i < 50000; i++)
-    initializerTestString += ",a"+i+"="+i;
-initializerTestString += ";return true;";
-
-var declarationTestString = "var a";
-for (var i = 0; i < 50000; i++)
-    declarationTestString += ",a"+i;
-declarationTestString += ";return true;";
-
-var commaExpressionTestString = "1";
-for (var i = 0; i < 50000; i++)
-    commaExpressionTestString += ",1";
-commaExpressionTestString += ";return true;";
-
-shouldBeTrue("new Function(initializerTestString)()");
-shouldBeTrue("new Function(declarationTestString)()");
-shouldBeTrue("new Function(commaExpressionTestString)()");