third_party/protobuf: Update to HEAD (83d681ee2c)

third_party/protobuf/appveyor.yml

Index: third_party/protobuf/appveyor.yml
diff --git a/third_party/protobuf/appveyor.yml b/third_party/protobuf/appveyor.yml
index c84ecae2f383346a33ec991a6211ea4abbc0e8ca..08d087b6992d8fbd1394441d4361ae0372c01cf4 100644
--- a/third_party/protobuf/appveyor.yml
+++ b/third_party/protobuf/appveyor.yml
@@ -11,13 +11,26 @@ environment:
   matrix:
     - language: cpp
       BUILD_DLL: ON
+      UNICODE: ON
 
     - language: csharp
 
+# Our build scripts run tests automatically; we don't want AppVeyor
+# to try to detect them itself.
+test: off
+
 install:
-  - ps: Start-FileDownload https://googlemock.googlecode.com/files/gmock-1.7.0.zip
-  - 7z x gmock-1.7.0.zip
-  - rename gmock-1.7.0 gmock
+  - curl -L -o release-1.7.0.zip https://github.com/google/googlemock/archive/release-1.7.0.zip
+  - 7z x release-1.7.0.zip
+  - del /Q release-1.7.0.zip
+  - rename googlemock-release-1.7.0 gmock
+  - curl -L -o release-1.7.0.zip "https://github.com/google/googletest/archive/release-1.7.0.zip"
+  - 7z x release-1.7.0.zip
+  - del /Q release-1.7.0.zip
+  - rename googletest-release-1.7.0 gtest
+  - move gtest gmock
+  - curl -L -o dotnetsdk.exe "https://go.microsoft.com/fwlink/?LinkID=809122"
+  - dotnetsdk.exe /install /quiet /norestart
 
 before_build:
   - if %platform%==Win32 set generator=Visual Studio 12