huge number of calls of stat function for non-existent files

thread named "Thread (pooled)" is doing huge number of calls of stat function for non-existent files according to strace during "Import Existing Project" of Chromium source code instead of creating/using list of existing files

stat("/mnt/tmp/chromium-55.0.2883.87/extensions/browser/guest_view/web_view/web_ui/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/browser/install/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/browser/kiosk/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/browser/mojo/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/browser/updater/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/browser/value_store/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/common/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/common/api/bluetooth/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/common/api/declarative/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/common/api/messaging/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/common/api/printer_provider/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/common/api/sockets/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/common/features/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/common/guest_view/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/common/manifest_handlers/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/common/permissions/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/components/javascript_dialog_extensions_client/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/components/native_app_window/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/renderer/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/renderer/api/automation/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/renderer/api/display_source/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/renderer/api/display_source/wifi_display/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/renderer/guest_view/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/renderer/guest_view/mime_handler_view/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/shell/app/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/shell/browser/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/shell/browser/api/identity/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/shell/browser/delegates/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/shell/common/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/shell/renderer/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/shell/test/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/shell/utility/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/test/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/extensions/utility/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/gin/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/gin/modules/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/gin/public/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/gin/test/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/google_apis/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/google_apis/drive/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/google_apis/gaia/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/google_apis/gcm/base/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/google_apis/gcm/engine/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/google_apis/gcm/monitoring/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/gpu/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/gpu/command_buffer/client/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/gpu/command_buffer/common/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/gpu/command_buffer/service/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/gpu/command_buffer/tests/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/gpu/config/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/gpu/GLES2/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/gpu/gles2_conform_support/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/gpu/gles2_conform_support/egl/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/gpu/gles2_conform_support/gtf/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/gpu/ipc/client/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/gpu/ipc/client/android/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/gpu/ipc/common/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)
stat("/mnt/tmp/chromium-55.0.2883.87/gpu/ipc/common/android/ui/views/test/test_views_delegate.h", 0x3568d119190) = -1 ENOENT (No such file or directory)