Support animating <time> custom properties

third_party/WebKit/Source/core/animation/BUILD.gn

 # Copyright 2016 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//third_party/WebKit/Source/core/core.gni")
 
 blink_core_sources("animation") {
   split_count = 5
 
   sources = [
@@ skipping 59 matching lines @@
     "CSSRotateInterpolationType.cpp",
     "CSSRotateInterpolationType.h",
     "CSSScaleInterpolationType.cpp",
     "CSSScaleInterpolationType.h",
     "CSSShadowListInterpolationType.cpp",
     "CSSShadowListInterpolationType.h",
     "CSSSizeListInterpolationType.cpp",
     "CSSSizeListInterpolationType.h",
     "CSSTextIndentInterpolationType.cpp",
     "CSSTextIndentInterpolationType.h",
+    "CSSTimeInterpolationType.cpp",
+    "CSSTimeInterpolationType.h",
     "CSSTransformInterpolationType.cpp",
     "CSSTransformInterpolationType.h",
     "CSSTransformOriginInterpolationType.h",
     "CSSTranslateInterpolationType.cpp",
     "CSSTranslateInterpolationType.h",
     "CSSValueInterpolationType.cpp",
     "CSSValueInterpolationType.h",
     "CSSVisibilityInterpolationType.cpp",
     "CSSVisibilityInterpolationType.h",
     "ColorPropertyFunctions.cpp",
@@ skipping 174 matching lines @@
     "css/CSSTimingData.h",
     "css/CSSTransitionData.cpp",
     "css/CSSTransitionData.h",
   ]
 
   configs += [
     # TODO(jschuh): crbug.com/167187 fix size_t to int truncations.
     "//build/config/compiler:no_size_t_to_int_warning",
   ]
 }