Fix overly-strict parameter checking of _getCallSiteData.

runtime/observatory/lib/src/elements/heap_profile.dart

Index: runtime/observatory/lib/src/elements/heap_profile.dart
diff --git a/runtime/observatory/lib/src/elements/heap_profile.dart b/runtime/observatory/lib/src/elements/heap_profile.dart
index c5dbc7621036193e92c69a652c86c3c8f18afb61..25b5d5411c616edd039997f4eec52a029e9cf7a2 100644
--- a/runtime/observatory/lib/src/elements/heap_profile.dart
+++ b/runtime/observatory/lib/src/elements/heap_profile.dart
@@ -235,6 +235,7 @@ class HeapProfileElement extends ObservatoryElement {
       cell.text = classTable.getFormattedValue(rowIndex, i);
       if (i > 1) {  // Numbers.
         cell.style.textAlign = 'right';
+        cell.style.paddingLeft = '1em';
       }
     }
   }