Issue #2688 - Don't apply auto min-sizing when flex max-sizing.

A grid item spanning multiple grid rows/columns which include a flexible
track should not participate in the auto min-sizing calculation.

Resolves #2688

Author: wolfbeast

layout/generic/nsGridContainerFrame.cpp

@@ -4519,6 +4519,7 @@ nsGridContainerFrame::Tracks::ResolveIntrinsicSize(
 
       // Check if we need to apply "Automatic Minimum Size" and cache it.
       if ((state & TrackSize::eAutoMinSizing) &&
+          !(state & TrackSize::eFlexMaxSizing) &&
           gridItem.ShouldApplyAutoMinSize(wm, mAxis, aPercentageBasis)) {
         gridItem.mState[mAxis] |= ItemState::eApplyAutoMinSize;
       }