cmake build: Disable clangpchmanagerbackend and refactoringbackend

By default. Previously only the corresponding plugins were disabled, but
not even building the backends makes more sense.

Change-Id: I36d61869a3050f37da1f480dea89e7539dda599a
Reviewed-by: Cristian Adam <cristian.adam@qt.io>
Reviewed-by: Marco Bubke <marco.bubke@qt.io>

cmake/QtCreatorAPI.cmake

@@ -541,7 +541,7 @@ endfunction()
 
 function(add_qtc_executable name)
   cmake_parse_arguments(_arg "SKIP_INSTALL;SKIP_TRANSLATION;ALLOW_ASCII_CASTS"
-    "DESTINATION;COMPONENT"
+    "DESTINATION;COMPONENT;BUILD_DEFAULT"
     "DEPENDS;DEFINES;INCLUDES;SOURCES;EXPLICIT_MOC;SKIP_AUTOMOC;EXTRA_TRANSLATIONS;PROPERTIES" ${ARGN})
 
   if ($_arg_UNPARSED_ARGUMENTS)
@@ -556,7 +556,11 @@ function(add_qtc_executable name)
   update_cached_list(__QTC_EXECUTABLES "${name}")
 
   string(TOUPPER "BUILD_EXECUTABLE_${name}" _build_executable_var)
+  if (DEFINED _arg_BUILD_DEFAULT)
+    set(_build_executable_default ${_arg_BUILD_DEFAULT})
+  else()
     set(_build_executable_default ${BUILD_EXECUTABLES_BY_DEFAULT})
+  endif()
   if (DEFINED ENV{QTC_${_build_executable_var}})
     set(_build_executable_default "$ENV{QTC_${_build_executable_var}}")
   endif()

src/plugins/clangpchmanager/CMakeLists.txt

@@ -1,6 +1,5 @@
 add_qtc_plugin(ClangPchManager
-  BUILD_DEFAULT OFF
-  CONDITION TARGET libclang
+  CONDITION TARGET libclang AND TARGET clangpchmanagerbackend
   DEPENDS ClangSupport CPlusPlus
   DEFINES CLANGPCHMANAGER_LIB
   PLUGIN_DEPENDS Core CppTools

src/plugins/clangrefactoring/CMakeLists.txt

@@ -1,6 +1,5 @@
 add_qtc_plugin(ClangRefactoring
-  BUILD_DEFAULT OFF
-  CONDITION TARGET libclang
+  CONDITION TARGET libclang AND TARGET clangrefactoringbackend
   DEPENDS ClangSupport CPlusPlus
   PLUGIN_DEPENDS Core CppTools TextEditor ClangPchManager
   SOURCES ${TEST_SOURCES}

src/tools/clangpchmanagerbackend/CMakeLists.txt

@@ -1,6 +1,7 @@
 add_subdirectory(source)
 
 add_qtc_executable(clangpchmanagerbackend
+  BUILD_DEFAULT OFF
   DEPENDS
     clangrefactoringbackend_lib clangpchmanagerbackend_lib
     Sqlite ClangSupport

src/tools/clangrefactoringbackend/CMakeLists.txt

@@ -1,6 +1,7 @@
 add_subdirectory(source)
 
 add_qtc_executable(clangrefactoringbackend
+  BUILD_DEFAULT OFF
   DEPENDS
     clangrefactoringbackend_lib Sqlite ClangSupport
   SOURCES