Fix background-size auto when no intrinsic size

According to the spec, https://drafts.csswg.org/css-backgrounds-3/#background-size, a background-size of "auto" with no intrinsic ratio or size should use 100% for the auto value. Instead we were using the positioning area's intrinsic ratio. Fix it. R=fmalita@chromium.org BUG=828842 Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel;master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2 Change-Id: Ia8d665ff2c725c9e40a89c0e160584feedc41b86 Reviewed-on: https://chromium-review.googlesource.com/996214 Commit-Queue: Stephen Chenney <schenney@chromium.org> Reviewed-by: Florin Malita <fmalita@chromium.org> Cr-Commit-Position: refs/heads/master@{#548596}

Fix background-size auto when no intrinsic size
According to the spec, https://drafts.csswg.org/css-backgrounds-3/#background-size, a background-size of "auto" with no intrinsic ratio or size should use 100% for the auto value. Instead we were using the positioning area's intrinsic ratio. Fix it. R=fmalita@chromium.org BUG=828842 Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel;master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2 Change-Id: Ia8d665ff2c725c9e40a89c0e160584feedc41b86 Reviewed-on: https://chromium-review.googlesource.com/996214 Commit-Queue: Stephen Chenney <schenney@chromium.org> Reviewed-by: Florin Malita <fmalita@chromium.org> Cr-Commit-Position: refs/heads/master@{#548596}
48c774d1 · Stephen Chenney · Commit Bot · 29cc37fa · 48c774d1 · 48c774d1
Commit 48c774d1 authored Apr 05, 2018 by Stephen Chenney Committed by Commit Bot Apr 05, 2018
5 changed files
--- a/third_party/WebKit/LayoutTests/css3/background/background-auto-no-intrinsic-expected.html
+++ b/third_party/WebKit/LayoutTests/css3/background/background-auto-no-intrinsic-expected.html
+<!DOCTYPE html>
+<style>
+  div {
+    background-image: radial-gradient(red, yellow, green);
+    background-repeat: no-repeat;
+    border: solid 1px black;
+    margin: 10px;
+  }
+  .horizontal {
+    background-size: 100% 50%;
+    width: 200px;
+    height: 100px;
+  }
+  .vertical {
+    background-size: 50% 100%;
+    width: 100px;
+    height: 200px;
+  }
+</style>
+<div class="horizontal">
+</div>
+<div class="vertical">
+</div>
--- a/third_party/WebKit/LayoutTests/css3/background/background-auto-no-intrinsic.html
+++ b/third_party/WebKit/LayoutTests/css3/background/background-auto-no-intrinsic.html
+<!DOCTYPE html>
+<style>
+  div {
+    background-image: radial-gradient(red, yellow, green);
+    background-repeat: no-repeat;
+    border: solid 1px black;
+    margin: 10px;
+  }
+  .horizontal {
+    background-size: auto 50%;
+    width: 200px;
+    height: 100px;
+  }
+  .vertical {
+    background-size: 50% auto;
+    width: 100px;
+    height: 200px;
+  }
+</style>
+<div class="horizontal">
+</div>
+<div class="vertical">
+</div>
--- a/third_party/WebKit/LayoutTests/platform/mac/css3/masking/mask-luminance-gradient-expected.png
+++ b/third_party/WebKit/LayoutTests/platform/mac/css3/masking/mask-luminance-gradient-expected.png
--- a/third_party/WebKit/LayoutTests/platform/win/css3/masking/mask-luminance-gradient-expected.png
+++ b/third_party/WebKit/LayoutTests/platform/win/css3/masking/mask-luminance-gradient-expected.png
--- a/third_party/WebKit/Source/core/paint/BackgroundImageGeometry.cpp
+++ b/third_party/WebKit/Source/core/paint/BackgroundImageGeometry.cpp
@@ -87,7 +87,11 @@ LayoutSize CalculateFillTileSize(const LayoutBoxModelObject& obj,
      // If one of the values is auto we have to use the appropriate
      // scale to maintain our aspect ratio.
      if (layer_width.IsAuto() && !layer_height.IsAuto()) {
-        if (image_intrinsic_size.Height()) {
+        if (image->ImageHasRelativeSize()) {
+          // Spec says that auto should be 100% in the absence of
+          // an intrinsic ratio or size.
+          tile_size.SetWidth(positioning_area_size.Width());
+        } else if (image_intrinsic_size.Height()) {
          LayoutUnit adjusted_width = image_intrinsic_size.Width() *
                                      tile_size.Height() /
                                      image_intrinsic_size.Height();
@@ -96,7 +100,11 @@ LayoutSize CalculateFillTileSize(const LayoutBoxModelObject& obj,
          tile_size.SetWidth(adjusted_width);
        }
      } else if (!layer_width.IsAuto() && layer_height.IsAuto()) {
-        if (image_intrinsic_size.Width()) {
+        if (image->ImageHasRelativeSize()) {
+          // Spec says that auto should be 100% in the absence of
+          // an intrinsic ratio or size.
+          tile_size.SetHeight(positioning_area_size.Height());
+        } else if (image_intrinsic_size.Width()) {
          LayoutUnit adjusted_height = image_intrinsic_size.Height() *
                                       tile_size.Width() /
                                       image_intrinsic_size.Width();