Move the Linux runner into a subdirectory (#153812)

Fixes flutter/flutter#60213

Author: robert-ancell

packages/flutter_tools/templates/app_shared/linux.tmpl/CMakeLists.txt.tmpl

@@ -1,5 +1,5 @@
 # Project-level configuration.
-cmake_minimum_required(VERSION 3.10)
+cmake_minimum_required(VERSION 3.13)
 project(runner LANGUAGES CXX)
 
 # The name of the executable created for the application. Change this to change
@@ -54,25 +54,8 @@ add_subdirectory(${FLUTTER_MANAGED_DIR})
 find_package(PkgConfig REQUIRED)
 pkg_check_modules(GTK REQUIRED IMPORTED_TARGET gtk+-3.0)
 
-add_definitions(-DAPPLICATION_ID="${APPLICATION_ID}")
-
-# Define the application target. To change its name, change BINARY_NAME above,
-# not the value here, or `flutter run` will no longer work.
-#
-# Any new source files that you add to the application should be added here.
-add_executable(${BINARY_NAME}
-  "main.cc"
-  "my_application.cc"
-  "${FLUTTER_MANAGED_DIR}/generated_plugin_registrant.cc"
-)
-
-# Apply the standard set of build settings. This can be removed for applications
-# that need different build settings.
-apply_standard_settings(${BINARY_NAME})
-
-# Add dependency libraries. Add any application-specific dependencies here.
-target_link_libraries(${BINARY_NAME} PRIVATE flutter)
-target_link_libraries(${BINARY_NAME} PRIVATE PkgConfig::GTK)
+# Application build; see runner/CMakeLists.txt.
+add_subdirectory("runner")
 
 # Run the Flutter tool portions of the build. This must not be removed.
 add_dependencies(${BINARY_NAME} flutter_assemble)

packages/flutter_tools/templates/app_shared/linux.tmpl/runner/CMakeLists.txt

@@ -0,0 +1,26 @@
+cmake_minimum_required(VERSION 3.13)
+project(runner LANGUAGES CXX)
+
+# Define the application target. To change its name, change BINARY_NAME in the
+# top-level CMakeLists.txt, not the value here, or `flutter run` will no longer
+# work.
+#
+# Any new source files that you add to the application should be added here.
+add_executable(${BINARY_NAME}
+  "main.cc"
+  "my_application.cc"
+  "${FLUTTER_MANAGED_DIR}/generated_plugin_registrant.cc"
+)
+
+# Apply the standard set of build settings. This can be removed for applications
+# that need different build settings.
+apply_standard_settings(${BINARY_NAME})
+
+# Add preprocessor definitions for the application ID.
+add_definitions(-DAPPLICATION_ID="${APPLICATION_ID}")
+
+# Add dependency libraries. Add any application-specific dependencies here.
+target_link_libraries(${BINARY_NAME} PRIVATE flutter)
+target_link_libraries(${BINARY_NAME} PRIVATE PkgConfig::GTK)
+
+target_include_directories(${BINARY_NAME} PRIVATE "${CMAKE_SOURCE_DIR}")

packages/flutter_tools/templates/app_shared/linux.tmpl/main.cc renamed to packages/flutter_tools/templates/app_shared/linux.tmpl/runner/main.cc

@@ -87,10 +87,11 @@
         "templates/app_shared/linux.tmpl/.gitignore",
         "templates/app_shared/linux.tmpl/CMakeLists.txt.tmpl",
         "templates/app_shared/linux.tmpl/flutter/CMakeLists.txt",
-        "templates/app_shared/linux.tmpl/main.cc",
-        "templates/app_shared/linux.tmpl/my_application.cc",
-        "templates/app_shared/linux.tmpl/my_application.cc.tmpl",
-        "templates/app_shared/linux.tmpl/my_application.h",
+        "templates/app_shared/linux.tmpl/runner/CMakeLists.txt",
+        "templates/app_shared/linux.tmpl/runner/main.cc",
+        "templates/app_shared/linux.tmpl/runner/my_application.cc",
+        "templates/app_shared/linux.tmpl/runner/my_application.cc.tmpl",
+        "templates/app_shared/linux.tmpl/runner/my_application.h",
         "templates/app_shared/macos.tmpl/.gitignore",
         "templates/app_shared/macos.tmpl/Flutter/Flutter-Debug.xcconfig",
         "templates/app_shared/macos.tmpl/Flutter/Flutter-Release.xcconfig",