Generate hashcode on the java types.

editor/tools/plugins/com.google.dart.server/src/com/google/dart/server/generated/types/SourceEdit.java

Index: editor/tools/plugins/com.google.dart.server/src/com/google/dart/server/generated/types/SourceEdit.java
diff --git a/editor/tools/plugins/com.google.dart.server/src/com/google/dart/server/generated/types/SourceEdit.java b/editor/tools/plugins/com.google.dart.server/src/com/google/dart/server/generated/types/SourceEdit.java
index e3fbbf0570be6b3b6799d7ee412759e483c4f690..a561d6e13c3929fc96e089823aa234bb922610a1 100644
--- a/editor/tools/plugins/com.google.dart.server/src/com/google/dart/server/generated/types/SourceEdit.java
+++ b/editor/tools/plugins/com.google.dart.server/src/com/google/dart/server/generated/types/SourceEdit.java
@@ -26,6 +26,7 @@ import com.google.gson.JsonArray;
 import com.google.gson.JsonElement;
 import com.google.gson.JsonObject;
 import com.google.gson.JsonPrimitive;
+import org.apache.commons.lang3.builder.HashCodeBuilder;
 import java.util.ArrayList;
 import java.util.Iterator;
 import org.apache.commons.lang3.StringUtils;
@@ -145,6 +146,16 @@ public class SourceEdit {
     return replacement;
   }
 
+  @Override
+  public int hashCode() {
+    HashCodeBuilder builder = new HashCodeBuilder();
+    builder.append(offset);
+    builder.append(length);
+    builder.append(replacement);
+    builder.append(id);
+    return builder.toHashCode();
+  }
+
   public JsonObject toJson() {
     JsonObject jsonObject = new JsonObject();
     jsonObject.addProperty("offset", offset);