ninja: Add Swift compile args for dependencies

Essential when using a modulemap to specify a C header, and needing the
include path to be set up correctly.

mesonbuild/backend/ninjabackend.py

@@ -2186,6 +2186,10 @@ def generate_swift_target(self, target):
                 if d.build is not None:
                     buildtreedir = os.path.normpath(os.path.join(self.environment.get_build_dir(), d.build))
                     compile_args += swiftc.get_include_args(buildtreedir, i.is_system)
+        for dep in reversed(target.get_external_deps()):
+            if not dep.found():
+                continue
+            compile_args += swiftc.get_dependency_compile_args(dep)
         compile_args += target.get_extra_args('swift')
         link_args = swiftc.get_output_args(os.path.join(self.environment.get_build_dir(), self.get_target_filename(target)))
         link_args += self.build.get_project_link_args(swiftc, target.subproject, target.for_machine)