Translate viewport related meta tags into @viewport descriptors as suggested by the CSS Device Adap…

Source/core/page/UseCounter.cpp

Index: Source/core/page/UseCounter.cpp
diff --git a/Source/core/page/UseCounter.cpp b/Source/core/page/UseCounter.cpp
index 1f4aa00f4113ee4af6451f3e49b9870f0bf8e058..e085de62efc8b13aeeb7d0941073f43d40202d45 100644
--- a/Source/core/page/UseCounter.cpp
+++ b/Source/core/page/UseCounter.cpp
@@ -488,6 +488,8 @@ static int mapCSSPropertyIdToCSSSampleId(int id)
     case CSSPropertyMixBlendMode: return 420;
     case CSSPropertyTouchAction: return 421;
     case CSSPropertyGridArea: return 422;
+    case CSSPropertyInternalTargetDensity: return 423;
+    case CSSPropertyInternalPriority: return 424;
 
     // Add new features above this line (don't change the assigned numbers of the existing
     // items) and update maximumCSSSampleId() with the new maximum value.
@@ -502,7 +504,7 @@ static int mapCSSPropertyIdToCSSSampleId(int id)
     return 0;
 }
 
-static int maximumCSSSampleId() { return 422; }
+static int maximumCSSSampleId() { return 424; }
 
 UseCounter::UseCounter()
 {