Allow booleans and number to be deserialized into a "String" field/object.

gson/src/main/java/com/google/gson/JsonPrimitive.java

@@ -166,7 +166,13 @@ public final class JsonPrimitive extends JsonElement {
    */
   @Override
   public String getAsString() {
-    return (String) value;
+    if (isNumber()) {
+      return getAsNumber().toString();
+    } else if (isBoolean()) {
+      return getAsBooleanWrapper().toString();
+    } else {
+      return (String) value;
+    }
   }
 
   /**

gson/src/test/java/com/google/gson/functional/ObjectTest.java

@@ -542,4 +542,14 @@ public class ObjectTest extends TestCase {
     assertTrue(bag.booleanValue);
     assertEquals("bar", bag.stringValue);
   }
+  
+  public void testStringFieldWithNumberValueDeserialization() {
+    String json = "{\"stringValue\":1}";
+    BagOfPrimitives bag = gson.fromJson(json, BagOfPrimitives.class);
+    assertEquals("1", bag.stringValue);
+    
+    json = "{\"stringValue\":true}";
+    bag = gson.fromJson(json, BagOfPrimitives.class);
+    assertEquals("true", bag.stringValue);
+  }
 }