make translate and scale interpolations return z-preserving OperationType

Set the OperationType in TransformOperation::Blend() according so that
it is a 3D operation type iff either of the blended values are
(previous behavior was to use the second value and ignore the first).
This makes Is3DOperation() work for interpolated operations stops
z values getting dropped during serialization.

Bug: 1057307
Change-Id: Ibcbb3125660ab172a0f65f08b8ccd67534cdd665
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2102640Reviewed-by: Kevin Ellis <kevers@chromium.org>
Reviewed-by: Robert Flack <flackr@chromium.org>
Reviewed-by: Ian Vollick <vollick@chromium.org>
Commit-Queue: George Steel <gtsteel@chromium.org>
Cr-Commit-Position: refs/heads/master@{#752071}

third_party/blink/renderer/platform/transforms/scale_transform_operation.cc

@@ -76,9 +76,11 @@ scoped_refptr<TransformOperation> ScaleTransformOperation::Blend(
   double from_x = from_op ? from_op->x_ : 1.0;
   double from_y = from_op ? from_op->y_ : 1.0;
   double from_z = from_op ? from_op->z_ : 1.0;
+
+  bool is_3d = Is3DOperation() || (from && from->Is3DOperation());
   return ScaleTransformOperation::Create(
       blink::Blend(from_x, x_, progress), blink::Blend(from_y, y_, progress),
-      blink::Blend(from_z, z_, progress), type_);
+      blink::Blend(from_z, z_, progress), is_3d ? kScale3D : kScale);
 }
 
 bool ScaleTransformOperation::CanBlendWith(

third_party/blink/renderer/platform/transforms/translate_transform_operation.cc

@@ -46,15 +46,15 @@ TransformOperation::OperationType GetTypeForTranslate(const Length& x,
   bool x_zero = x.IsZero();
   bool y_zero = x.IsZero();
   bool z_zero = !z;
-  if (!x_zero && !y_zero && !z_zero)
-    return TransformOperation::kTranslate3D;
   if (y_zero && z_zero)
     return TransformOperation::kTranslateX;
   if (x_zero && z_zero)
     return TransformOperation::kTranslateY;
   if (x_zero && y_zero)
     return TransformOperation::kTranslateZ;
-  return TransformOperation::kTranslate;
+  if (z_zero)
+    return TransformOperation::kTranslate;
+  return TransformOperation::kTranslate3D;
 }
 }  // namespace
 
@@ -89,10 +89,12 @@ scoped_refptr<TransformOperation> TranslateTransformOperation::Blend(
   const Length& from_x = from_op ? from_op->x_ : zero_length;
   const Length& from_y = from_op ? from_op->y_ : zero_length;
   double from_z = from_op ? from_op->z_ : 0;
+
+  bool is_3d = Is3DOperation() || (from && from->Is3DOperation());
   return TranslateTransformOperation::Create(
       x_.Blend(from_x, progress, kValueRangeAll),
       y_.Blend(from_y, progress, kValueRangeAll),
-      blink::Blend(from_z, z_, progress), type_);
+      blink::Blend(from_z, z_, progress), is_3d ? kTranslate3D : kTranslate);
 }
 
 bool TranslateTransformOperation::CanBlendWith(

third_party/blink/web_tests/external/wpt/css/css-transforms/animation/transform-interpolation-computed-value-expected.txt

 This is a testharness.js-based test.
-Found 87 tests; 29 PASS, 58 FAIL, 0 TIMEOUT, 0 NOTRUN.
+Found 87 tests; 34 PASS, 53 FAIL, 0 TIMEOUT, 0 NOTRUN.
 FAIL Interpolation between translateX(0px) and translateX(50px) gives the correct computed value halfway according to computedStyleMap. assert_equals: The value at 50% progress is as expected expected "translateX(25px)" but got "translate(25px, 0px)"
 FAIL Interpolation between translateX(0px) and translateX(50px) gives the correct computed value halfway according to computedStyleMap with zoom active. assert_equals: The value at 50% progress is as expected expected "translateX(25px)" but got "translate(25px, 0px)"
 FAIL Interpolation between translateX(0px) and translateX(50px) gives the correct computed value halfway according to commitStyles. assert_equals: The value at 50% progress is as expected expected "translateX(25px)" but got "matrix(1, 0, 0, 1, 25, 0)"
@@ -15,8 +15,8 @@ FAIL Interpolation between translateX(50px) and translateY(50px) gives the corre
 PASS Interpolation between translateX(50px) and translateZ(50px) gives the correct computed value halfway according to computedStyleMap.
 FAIL Interpolation between translateX(50px) and translateZ(50px) gives the correct computed value halfway according to computedStyleMap with zoom active. assert_equals: The value at 50% progress is as expected expected "translate3d(25px, 0px, 25px)" but got "translate3d(25px, 0px, 31.25px)"
 FAIL Interpolation between translateX(50px) and translateZ(50px) gives the correct computed value halfway according to commitStyles. assert_equals: The value at 50% progress is as expected expected "translate3d(25px, 0px, 25px)" but got "matrix3d(1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 25, 0, 25, 1)"
-FAIL Interpolation between translateZ(50px) and translateX(50px) gives the correct computed value halfway according to computedStyleMap. assert_equals: The value at 50% progress is as expected expected "translate3d(25px, 0px, 25px)" but got "translate(25px, 0px)"
-FAIL Interpolation between translateZ(50px) and translateX(50px) gives the correct computed value halfway according to computedStyleMap with zoom active. assert_equals: The value at 50% progress is as expected expected "translate3d(25px, 0px, 25px)" but got "translate(25px, 0px)"
+PASS Interpolation between translateZ(50px) and translateX(50px) gives the correct computed value halfway according to computedStyleMap.
+FAIL Interpolation between translateZ(50px) and translateX(50px) gives the correct computed value halfway according to computedStyleMap with zoom active. assert_equals: The value at 50% progress is as expected expected "translate3d(25px, 0px, 25px)" but got "translate3d(25px, 0px, 31.25px)"
 FAIL Interpolation between translateZ(50px) and translateX(50px) gives the correct computed value halfway according to commitStyles. assert_equals: The value at 50% progress is as expected expected "translate3d(25px, 0px, 25px)" but got "matrix3d(1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 25, 0, 25, 1)"
 FAIL Interpolation between translateZ(-50px) and translateZ(50px) gives the correct computed value halfway according to computedStyleMap. assert_equals: The value at 50% progress is as expected expected "translateZ(0px)" but got "translate3d(0px, 0px, 0px)"
 FAIL Interpolation between translateZ(-50px) and translateZ(50px) gives the correct computed value halfway according to computedStyleMap with zoom active. assert_equals: The value at 50% progress is as expected expected "translateZ(0px)" but got "translate3d(0px, 0px, 0px)"
@@ -57,8 +57,8 @@ FAIL Interpolation between scaleX(2) and scaleY(2) gives the correct computed va
 PASS Interpolation between scaleX(2) and scaleY(3) gives the correct computed value halfway according to computedStyleMap.
 PASS Interpolation between scaleX(2) and scaleY(3) gives the correct computed value halfway according to computedStyleMap with zoom active.
 FAIL Interpolation between scaleX(2) and scaleY(3) gives the correct computed value halfway according to commitStyles. assert_equals: The value at 50% progress is as expected expected "scale(1.5, 2)" but got "matrix(1.5, 0, 0, 2, 0, 0)"
-FAIL Interpolation between scaleZ(1) and scale(2) gives the correct computed value halfway according to computedStyleMap. assert_equals: The value at 50% progress is as expected expected "scale3d(1.5, 1.5, 1)" but got "scale(1.5, 1.5)"
-FAIL Interpolation between scaleZ(1) and scale(2) gives the correct computed value halfway according to computedStyleMap with zoom active. assert_equals: The value at 50% progress is as expected expected "scale3d(1.5, 1.5, 1)" but got "scale(1.5, 1.5)"
+PASS Interpolation between scaleZ(1) and scale(2) gives the correct computed value halfway according to computedStyleMap.
+PASS Interpolation between scaleZ(1) and scale(2) gives the correct computed value halfway according to computedStyleMap with zoom active.
 FAIL Interpolation between scaleZ(1) and scale(2) gives the correct computed value halfway according to commitStyles. assert_equals: The value at 50% progress is as expected expected "scale3d(1.5, 1.5, 1)" but got "matrix(1.5, 0, 0, 1.5, 0, 0)"
 PASS Interpolation between scale(1, 2) and scale(3, 4) gives the correct computed value halfway according to computedStyleMap.
 PASS Interpolation between scale(1, 2) and scale(3, 4) gives the correct computed value halfway according to computedStyleMap with zoom active.
@@ -66,8 +66,8 @@ FAIL Interpolation between scale(1, 2) and scale(3, 4) gives the correct compute
 PASS Interpolation between scale3d(1, 2, 3) and scale3d(4, 5, 6) gives the correct computed value halfway according to computedStyleMap.
 PASS Interpolation between scale3d(1, 2, 3) and scale3d(4, 5, 6) gives the correct computed value halfway according to computedStyleMap with zoom active.
 FAIL Interpolation between scale3d(1, 2, 3) and scale3d(4, 5, 6) gives the correct computed value halfway according to commitStyles. assert_equals: The value at 50% progress is as expected expected "scale3d(2.5, 3.5, 4.5)" but got "matrix3d(2.5, 0, 0, 0, 0, 3.5, 0, 0, 0, 0, 4.5, 0, 0, 0, 0, 1)"
-FAIL Interpolation between scale3d(1, 2, 3) and scale(4, 5) gives the correct computed value halfway according to computedStyleMap. assert_equals: The value at 50% progress is as expected expected "scale3d(2.5, 3.5, 2)" but got "scale(2.5, 3.5)"
-FAIL Interpolation between scale3d(1, 2, 3) and scale(4, 5) gives the correct computed value halfway according to computedStyleMap with zoom active. assert_equals: The value at 50% progress is as expected expected "scale3d(2.5, 3.5, 2)" but got "scale(2.5, 3.5)"
+PASS Interpolation between scale3d(1, 2, 3) and scale(4, 5) gives the correct computed value halfway according to computedStyleMap.
+PASS Interpolation between scale3d(1, 2, 3) and scale(4, 5) gives the correct computed value halfway according to computedStyleMap with zoom active.
 FAIL Interpolation between scale3d(1, 2, 3) and scale(4, 5) gives the correct computed value halfway according to commitStyles. assert_equals: The value at 50% progress is as expected expected "scale3d(2.5, 3.5, 2)" but got "matrix3d(2.5, 0, 0, 0, 0, 3.5, 0, 0, 0, 0, 2, 0, 0, 0, 0, 1)"
 PASS Interpolation between scale(1, 2) and scale3d(3, 4, 5) gives the correct computed value halfway according to computedStyleMap.
 PASS Interpolation between scale(1, 2) and scale3d(3, 4, 5) gives the correct computed value halfway according to computedStyleMap with zoom active.