[css-grid] Only force full invalidation when grid item data change

third_party/WebKit/Source/core/style/ComputedStyle.cpp

Index: third_party/WebKit/Source/core/style/ComputedStyle.cpp
diff --git a/third_party/WebKit/Source/core/style/ComputedStyle.cpp b/third_party/WebKit/Source/core/style/ComputedStyle.cpp
index d4ecea553149fae5db25b9120f62e06e9f4021a2..bcc0367d2348a7994c4a947d56a3d764c2d6be74 100644
--- a/third_party/WebKit/Source/core/style/ComputedStyle.cpp
+++ b/third_party/WebKit/Source/core/style/ComputedStyle.cpp
@@ -595,11 +595,17 @@ bool ComputedStyle::diffNeedsFullLayoutAndPaintInvalidation(const ComputedStyle&
             || m_rareNonInheritedData->textOverflow != other.m_rareNonInheritedData->textOverflow
             || m_rareNonInheritedData->m_shapeMargin != other.m_rareNonInheritedData->m_shapeMargin
             || m_rareNonInheritedData->m_order != other.m_rareNonInheritedData->m_order
-            || m_rareNonInheritedData->m_grid.get() != other.m_rareNonInheritedData->m_grid.get()
-            || m_rareNonInheritedData->m_gridItem.get() != other.m_rareNonInheritedData->m_gridItem.get()
             || m_rareNonInheritedData->hasFilters() != other.m_rareNonInheritedData->hasFilters())
             return true;
 
+        if (m_rareNonInheritedData->m_grid.get() != other.m_rareNonInheritedData->m_grid.get()
+            && *m_rareNonInheritedData->m_grid.get() != *other.m_rareNonInheritedData->m_grid.get())
+            return true;
+
+        if (m_rareNonInheritedData->m_gridItem.get() != other.m_rareNonInheritedData->m_gridItem.get()
+            && *m_rareNonInheritedData->m_gridItem.get() != *other.m_rareNonInheritedData->m_gridItem.get())
+            return true;
+
         if (m_rareNonInheritedData->m_deprecatedFlexibleBox.get() != other.m_rareNonInheritedData->m_deprecatedFlexibleBox.get()
             && *m_rareNonInheritedData->m_deprecatedFlexibleBox.get() != *other.m_rareNonInheritedData->m_deprecatedFlexibleBox.get())
             return true;