Update third_party/protobuf to protobuf-v3.0.0-beta-3

third_party/protobuf/csharp/src/Google.Protobuf.Test/Google.Protobuf.Test.csproj

 <?xml version="1.0" encoding="utf-8"?>
 <Project ToolsVersion="4.0" DefaultTargets="Build" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
   <PropertyGroup>
     <Configuration Condition=" '$(Configuration)' == '' ">Debug</Configuration>
     <Platform Condition=" '$(Platform)' == '' ">AnyCPU</Platform>
     <ProductVersion>9.0.30729</ProductVersion>
     <SchemaVersion>2.0</SchemaVersion>
     <ProjectGuid>{DD01ED24-3750-4567-9A23-1DB676A15610}</ProjectGuid>
     <OutputType>Library</OutputType>
     <AppDesignerFolder>Properties</AppDesignerFolder>
@@ skipping 37 matching lines @@
     <Optimize>true</Optimize>
     <OutputPath>bin\ReleaseSigned</OutputPath>
     <IntermediateOutputPath>obj\ReleaseSigned\</IntermediateOutputPath>
     <DefineConstants>TRACE;$(EnvironmentFlavor);$(EnvironmentTemplate)</DefineConstants>
     <ErrorReport>prompt</ErrorReport>
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     <NoStdLib>true</NoStdLib>
     <GenerateSerializationAssemblies>Off</GenerateSerializationAssemblies>
     <Prefer32Bit>false</Prefer32Bit>
     <SignAssembly>True</SignAssembly>
-    <AssemblyOriginatorKeyFile>C:\keys\Google.Protobuf.snk</AssemblyOriginatorKeyFile>
+    <AssemblyOriginatorKeyFile>..\..\keys\Google.Protobuf.snk</AssemblyOriginatorKeyFile>
   </PropertyGroup>
   <ItemGroup>
     <Reference Include="mscorlib" />
     <Reference Include="nunit.core, Version=2.6.4.14350, Culture=neutral, PublicKeyToken=96d09a1eb7f44a77, processorArchitecture=MSIL">
       <HintPath>..\packages\NUnitTestAdapter.2.0.0\lib\nunit.core.dll</HintPath>
       <Private>True</Private>
     </Reference>
     <Reference Include="nunit.core.interfaces, Version=2.6.4.14350, Culture=neutral, PublicKeyToken=96d09a1eb7f44a77, processorArchitecture=MSIL">
       <HintPath>..\packages\NUnitTestAdapter.2.0.0\lib\nunit.core.interfaces.dll</HintPath>
       <Private>True</Private>
@@ skipping 26 matching lines @@
     <Compile Include="Collections\MapFieldTest.cs" />
     <Compile Include="Collections\RepeatedFieldTest.cs" />
     <Compile Include="JsonFormatterTest.cs" />
     <Compile Include="JsonParserTest.cs" />
     <Compile Include="JsonTokenizerTest.cs" />
     <Compile Include="Reflection\DescriptorsTest.cs" />
     <Compile Include="Reflection\FieldAccessTest.cs" />
     <Compile Include="Reflection\TypeRegistryTest.cs" />
     <Compile Include="SampleEnum.cs" />
     <Compile Include="SampleMessages.cs" />
+    <Compile Include="TestProtos\ForeignMessagePartial.cs" />
     <Compile Include="TestProtos\MapUnittestProto3.cs" />
     <Compile Include="TestProtos\UnittestImportProto3.cs" />
     <Compile Include="TestProtos\UnittestImportPublicProto3.cs" />
     <Compile Include="TestProtos\UnittestIssues.cs" />
     <Compile Include="TestProtos\UnittestProto3.cs" />
     <Compile Include="DeprecatedMemberTest.cs" />
     <Compile Include="IssuesTest.cs" />
     <Compile Include="Properties\AssemblyInfo.cs" />
     <Compile Include="TestCornerCases.cs" />
     <Compile Include="TestProtos\UnittestWellKnownTypes.cs" />
     <Compile Include="WellKnownTypes\AnyTest.cs" />
     <Compile Include="WellKnownTypes\DurationTest.cs" />
+    <Compile Include="WellKnownTypes\FieldMaskTest.cs" />
     <Compile Include="WellKnownTypes\TimestampTest.cs" />
     <Compile Include="WellKnownTypes\WrappersTest.cs" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\Google.Protobuf\Google.Protobuf.csproj">
       <Project>{6908BDCE-D925-43F3-94AC-A531E6DF2591}</Project>
       <Name>Google.Protobuf</Name>
     </ProjectReference>
   </ItemGroup>
   <ItemGroup>
     <None Include="packages.config" />
   </ItemGroup>
   <ItemGroup>
     <Service Include="{82A7F48D-3B50-4B1E-B82E-3ADA8210C358}" />
   </ItemGroup>
   <ItemGroup />
   <Import Project="$(MSBuildToolsPath)\Microsoft.CSharp.targets" />
   <!-- To modify your build process, add your task inside one of the targets below and uncomment it. 
        Other similar extension points exist, see Microsoft.Common.targets.
   <Target Name="BeforeBuild">
   </Target>
   <Target Name="AfterBuild">
   </Target>
   -->
 </Project>