Don't use pairwise keyframe interpolation at fractions 0 and 1.

third_party/WebKit/LayoutTests/animations/composition/text-shadow-composition.html

Index: third_party/WebKit/LayoutTests/animations/composition/text-shadow-composition.html
diff --git a/third_party/WebKit/LayoutTests/animations/composition/text-shadow-composition.html b/third_party/WebKit/LayoutTests/animations/composition/text-shadow-composition.html
index 1f40b3fbe8c8c8490a2253acb93aa9e00e58c911..2525555a4141b829e15ded30f1b638bfd5e62b65 100644
--- a/third_party/WebKit/LayoutTests/animations/composition/text-shadow-composition.html
+++ b/third_party/WebKit/LayoutTests/animations/composition/text-shadow-composition.html
@@ -74,7 +74,7 @@ assertComposition({
   {at: -0.3, is: 'rgb(83, 96, 109) 8.3px 16.6px 24.9px, rgb(226, 252, 255) 22.6px 45.2px 67.8px, rgb(122, 174, 226) 12.2px 24.4px 36.6px, rgb(213, 226, 239) 21.3px 42.6px 63.9px, rgb(96, 122, 148) 9.6px 19.2px 28.8px, rgb(252, 255, 255) 25.2px 50.4px 75.6px'},
   {at: 0, is: 'rgb(110, 120, 130) 11px 22px 33px, rgb(220, 240, 255) 22px 44px 66px, rgb(140, 180, 220) 14px 28px 42px, rgb(210, 220, 230) 21px 42px 63px, rgb(120, 140, 160) 12px 24px 36px, rgb(240, 255, 255) 24px 48px 72px'},
   {at: 0.5, is: 'rgb(155, 160, 165) 15.5px 31px 46.5px, rgb(210, 220, 230) 21px 42px 63px, rgb(170, 190, 210) 17px 34px 51px, rgb(205, 210, 215) 20.5px 41px 61.5px, rgb(160, 170, 180) 16px 32px 48px, rgb(220, 240, 255) 22px 44px 66px'},
-  {at: 1, is: 'rgb(200, 200, 200) 20px 40px 60px, rgb(200, 200, 200) 20px 40px 60px'},
+  {at: 1, is: 'rgb(200, 200, 200) 20px 40px 60px'},
   {at: 1.5, is: 'rgba(255, 255, 255, 0.501961) 24.5px 49px 73.5px, rgba(255, 255, 255, 0.501961) 19px 38px 57px, rgba(255, 255, 255, 0.501961) 23px 46px 69px, rgba(255, 255, 255, 0.501961) 19.5px 39px 58.5px, rgba(255, 255, 255, 0.501961) 24px 48px 72px, rgba(255, 255, 255, 0.501961) 18px 36px 54px'},
 ]);
 </script>