[css-grid] Implement repeat(auto-fit)

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

Index: third_party/WebKit/Source/core/style/GridPositionsResolver.cpp
diff --git a/third_party/WebKit/Source/core/style/GridPositionsResolver.cpp b/third_party/WebKit/Source/core/style/GridPositionsResolver.cpp
index 23cb2441a32c27618d6fe0ee72511cd86234b7e0..fdd67771906704f42c210ab0e26976796ba52e43 100644
--- a/third_party/WebKit/Source/core/style/GridPositionsResolver.cpp
+++ b/third_party/WebKit/Source/core/style/GridPositionsResolver.cpp
@@ -34,7 +34,7 @@ NamedLineCollection::NamedLineCollection(const ComputedStyle& gridContainerStyle
     }
 
     if (!autoRepeatGridLineNames.isEmpty()) {
-        auto it = autoRepeatGridLineNames.find(namedLine);
+        auto it = m_repetitions ? autoRepeatGridLineNames.find(namedLine) : autoRepeatGridLineNames.end();
         m_autoRepeatNamedLinesIndexes = it == autoRepeatGridLineNames.end() ? nullptr : &it->value;
     }
 
@@ -327,7 +327,7 @@ static int resolveGridPositionFromStyle(const ComputedStyle& gridContainerStyle,
         if (explicitLines.hasNamedLines())
             return explicitLines.firstPosition();
 
-        ASSERT(!NamedLineCollection::isValidNamedLineOrArea(namedGridLine, gridContainerStyle, side));
+        DCHECK(!NamedLineCollection::isValidNamedLineOrArea(namedGridLine, gridContainerStyle, side) || !autoRepeatTracksCount);
         // If none of the above works specs mandate to assume that all the lines in the implicit grid have this name.
         return lastLine + 1;
     }