Manual fixes for Dart^2 analyzer

pkg/analyzer_experimental/lib/src/generated/java_core.dart

 library java.core;
 
 import "dart:math" as math;
 import "dart:uri";
 import "dart:collection" show ListBase;
 
 class JavaSystem {
   static int currentTimeMillis() {
     return (new DateTime.now()).millisecondsSinceEpoch;
   }
@@ skipping 301 matching lines @@
 
   void addLast(E value) {
     elements.add(value);
   }
 
   void addAll(Iterable<E> iterable) {
     elements.addAll(iterable);
   }
 
   void setAll(int index, Iterable<E> iterable) {
-    elements.setAll(iterable);
+    elements.setAll(index, iterable);
   }
 
   void sort([int compare(E a, E b)]) {
     elements.sort(compare);
   }
 
   int indexOf(E element, [int start = 0]) {
     return elements.indexOf(element, start);
   }
 
@@ skipping 122 matching lines @@
   return a.toLowerCase() == b.toLowerCase();
 }
 
 bool javaBooleanOr(bool a, bool b) {
   return a || b;
 }
 
 class JavaStringBuilder {
   StringBuffer sb = new StringBuffer();
   String toString() => sb.toString();
-  void append(x) {
+  JavaStringBuilder append(x) {
     sb.write(x);
+    return this;
   }
-  void appendChar(int c) {
+  JavaStringBuilder appendChar(int c) {
     sb.writeCharCode(c);
+    return this;
   }
   int get length => sb.length;
   void set length(int newLength) {
     if (newLength < 0) {
       throw new StringIndexOutOfBoundsException(newLength);
     }
     if (sb.length < newLength) {
       while (sb.length < newLength) {
         sb.writeCharCode(0);
       }
     } else if (sb.length > newLength) {
       var s = sb.toString().substring(0, newLength);
       sb = new StringBuffer(s);
     }
   }
   void clear() {
     sb = new StringBuffer();
   }
 }