Add option to externally build protobuf.

CMakeLists.txt

@@ -64,6 +64,7 @@ function (superbuild_find_projects var)
     paraviewwebflow
     paraviewwebvisualizer
     png
+    protobuf
     pythonattrs
     pythonautobahn
     pythonconstantly

projects/paraview.cmake

@@ -142,7 +142,7 @@ superbuild_add_project(paraview
   DEBUGGABLE
   DEFAULT_ON
   DEPENDS_OPTIONAL
-    adios2 cuda boost hdf5 matplotlib mpi numpy png
+    adios2 cuda boost hdf5 matplotlib mpi numpy png protobuf
     python python2 python3 qt5 visitbridge zlib silo las
     xdmf3 ospray vrpn vtkm tbb netcdf
     nlohmannjson
@@ -175,6 +175,7 @@ superbuild_add_project(paraview
     -DVISIT_BUILD_READER_Silo:BOOL=${silo_enabled}
     -DPARAVIEW_INSTALL_DEVELOPMENT_FILES:BOOL=${paraview_install_development_files}
     -DPARAVIEW_FREEZE_PYTHON:BOOL=${PARAVIEW_FREEZE_PYTHON}
+    -DVTK_MODULE_USE_EXTERNAL_ParaView_protobuf:BOOL=${protobuf_enabled}
     -DVTK_MODULE_USE_EXTERNAL_VTK_netcdf:BOOL=${netcdf_enabled}
     -DVTK_MODULE_USE_EXTERNAL_VTK_freetype:BOOL=${freetype_enabled}
     -DVTK_MODULE_USE_EXTERNAL_VTK_hdf5:BOOL=${hdf5_enabled}

projects/protobuf.cmake

+superbuild_add_project(protobuf
+  DEPENDS cxx11
+  DEPENDS_OPTIONAL zlib
+  CMAKE_ARGS
+    -DBUILD_SHARED_LIBS:BOOL=${BUILD_SHARED_LIBS}
+    -Dprotobuf_BUILD_TESTS:BOOL=OFF)

versions.cmake

@@ -202,3 +202,8 @@ superbuild_set_selectable_source(adios2
 superbuild_set_revision(libfabric
   URL     "http://www.paraview.org/files/dependencies/libfabric-1.8.0.tar.bz2"
   URL_MD5 "c19c257856cb6e5094e73bf727e2d76c")
+
+superbuild_set_revision(protobuf
+  GIT_REPOSITORY "https://github.com/protocolbuffers/protobuf"
+  GIT_TAG 2.7.0
+  SOURCE_SUBDIR cmake)