Fixed some static type warnings in vm core libraries

runtime/lib/integers.dart

Index: runtime/lib/integers.dart
diff --git a/runtime/lib/integers.dart b/runtime/lib/integers.dart
index 4d4759134b6a7ba6d6d4c4f6d76118fbc32193c7..102b597c1241914ba285f3a3eda0df23bb328782 100644
--- a/runtime/lib/integers.dart
+++ b/runtime/lib/integers.dart
@@ -141,8 +141,7 @@ class IntegerImplementation {
     if ((radix <= 1) || (radix > 16)) {
       throw "Bad radix: $radix";
     }
-    final bool isNegative = this < 0;
-    var value = isNegative ? -this : this;
+    var value = this.isNegative() ? -this : this;

[Ivan Posva, 2012/03/14 05:34:05]

Please maintain the code as it was with a local variable. If you really want to
avoid the hiding of the name then please use a different variable name:
final negative = this.isNegative();
var value = negative ? -this : this;
...
if (negative) {
  buffer.add("-");
}

Actually on second thought, I do like the name isNegative and there is a reason
why we allow shadowing.

[zundel, 2012/03/14 13:04:34]

np, I'll revert this. 

Background: the shadowing warning is not in the spec,we were thinking it could
be optionally flipped on/off for developers that wanted it (currently there is
no way to turn it off).

     List temp = new List();
     while (value > 0) {
       var digit = value % radix;
@@ -153,7 +152,7 @@ class IntegerImplementation {
       return "0";
     }
     StringBuffer buffer = new StringBuffer();
-    if (isNegative) buffer.add("-");
+    if (this.isNegative()) buffer.add("-");
     for (int i = temp.length - 1; i >= 0; i--) {
       buffer.add(table[temp[i]]);
     }