Resolve CSS url(...) non-<image> values against the correct base

third_party/WebKit/Source/modules/canvas2d/CanvasRenderingContext2DState.cpp

Index: third_party/WebKit/Source/modules/canvas2d/CanvasRenderingContext2DState.cpp
diff --git a/third_party/WebKit/Source/modules/canvas2d/CanvasRenderingContext2DState.cpp b/third_party/WebKit/Source/modules/canvas2d/CanvasRenderingContext2DState.cpp
index 17b4b39f12defdd116529aa1c96d2b49ac095d51..dcc455b8659eda3ccc7c754e942228e0c205f3db 100644
--- a/third_party/WebKit/Source/modules/canvas2d/CanvasRenderingContext2DState.cpp
+++ b/third_party/WebKit/Source/modules/canvas2d/CanvasRenderingContext2DState.cpp
@@ -284,6 +284,10 @@ sk_sp<SkImageFilter> CanvasRenderingContext2DState::getFilter(
     return nullptr;
 
   if (!m_resolvedFilter) {
+    // Update the filter value to the proper base URL if needed.
+    if (m_filterValue->mayContainUrl())
+      m_filterValue->reResolveUrl(styleResolutionHost->document());
+
     RefPtr<ComputedStyle> filterStyle = ComputedStyle::create();
     // Must set font in case the filter uses any font-relative units (em, ex)
     filterStyle->setFont(m_fontForFilter);