Tests and fixes for double-enumeration on AddRange and adding of null to PopsicleList
diff --git a/src/ProtocolBuffersLite.Test/TestProtos/UnitTestExtrasLiteProtoFile.cs b/src/ProtocolBuffersLite.Test/TestProtos/UnitTestExtrasLiteProtoFile.cs
index bc214e2..38d6ff8 100644
--- a/src/ProtocolBuffersLite.Test/TestProtos/UnitTestExtrasLiteProtoFile.cs
+++ b/src/ProtocolBuffersLite.Test/TestProtos/UnitTestExtrasLiteProtoFile.cs
@@ -1354,13 +1354,13 @@
           Email = other.Email;

         }

         if (other.codes_.Count != 0) {

-          base.AddRange(other.codes_, result.codes_);

+          result.codes_.Add(other.codes_);

         }

         if (other.phone_.Count != 0) {

-          base.AddRange(other.phone_, result.phone_);

+          result.phone_.Add(other.phone_);

         }

         if (other.addresses_.Count != 0) {

-          base.AddRange(other.addresses_, result.addresses_);

+          result.addresses_.Add(other.addresses_);

         }

           this.MergeExtensionFields(other);

         return this;

@@ -1500,7 +1500,7 @@
         return this;

       }

       public Builder AddRangeCodes(scg::IEnumerable<int> values) {

-        base.AddRange(values, result.codes_);

+        result.codes_.Add(values);

         return this;

       }

       public Builder ClearCodes() {

@@ -1538,7 +1538,7 @@
         return this;

       }

       public Builder AddRangePhone(scg::IEnumerable<global::Google.ProtocolBuffers.TestProtos.TestInteropPersonLite.Types.PhoneNumber> values) {

-        base.AddRange(values, result.phone_);

+        result.phone_.Add(values);

         return this;

       }

       public Builder ClearPhone() {

@@ -1576,7 +1576,7 @@
         return this;

       }

       public Builder AddRangeAddresses(scg::IEnumerable<global::Google.ProtocolBuffers.TestProtos.TestInteropPersonLite.Types.Addresses> values) {

-        base.AddRange(values, result.addresses_);

+        result.addresses_.Add(values);

         return this;

       }

       public Builder ClearAddresses() {