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 8d10626ffdb07eb3fb96f822844f4b2c4f3ccab0..45b6aae94f897ec7586332961962d2a564841f07 100644
--- a/Source/core/page/UseCounter.cpp
+++ b/Source/core/page/UseCounter.cpp
@@ -492,6 +492,8 @@ int UseCounter::mapCSSPropertyIdToCSSSampleIdForHistogram(int id)
     case CSSPropertyAnimationName: return 430;
     case CSSPropertyAnimationPlayState: return 431;
     case CSSPropertyAnimationTimingFunction: return 432;
+    case CSSPropertyInternalTargetDensity: return 433;
+    case CSSPropertyInternalPriority: return 434;
 
     // Add new features above this line (don't change the assigned numbers of the existing
     // items) and update maximumCSSSampleId() with the new maximum value.
@@ -506,7 +508,7 @@ int UseCounter::mapCSSPropertyIdToCSSSampleIdForHistogram(int id)
     return 0;
 }
 
-static int maximumCSSSampleId() { return 432; }
+static int maximumCSSSampleId() { return 434; }
 
 UseCounter::UseCounter()
 {