[enumification] Support "non-constant-to-constant" transition in enums (#1080)

At  9a73c4c we became much more precise about enumification, because
formerly we only pull int constant information through DroidDoc only in
the latest API.

Besides, we had been precise on which int fields are final and which aren't,
in API XML metadata.

Since we switched the information source to API XML metadata, such final
fields that were NOT final are strictly converted to enums only in the
constant-ified API Level.

That was regarded as regression at #1078 .

The solution to this situation is: treat them as constants.

To do so, now generate-const-list-2.cs is changed to NOT check if an int
field is final or not, until at the merge phase. Then we filter out those
non-constant fields (which are not much).

This uncovers those "formerly non constant" fields too. Fortunately such
fields didn't exist other than the ones at PR #1078 mentioned (this
generate-const-list-2.exe now prints out such fields now.)

Author: atsushieno

build-tools/enumification-helpers/generate-const-list-2.cs

@@ -8,9 +8,9 @@
 
 public class Driver
 {
-	class Constant {
+	class ConstantCandidate {
 		public string Package, ParentType, Level, FieldType, Name, Value;
-		public bool IsTypeInterface;
+		public bool IsTypeInterface, IsFinal;
 	}
 
 	static string GetApiLevel (string file)
@@ -30,15 +30,16 @@ public static void Main (string [] args)
 			.SelectMany (p => p.Elements ())
 			.SelectMany (t => t.Elements ("field"))
 			.Where (f => f.Attribute ("type")?.Value == "int")
-			.Where (f => f.Attribute ("final")?.Value == "true" && f.Attribute ("value") != null)
+			//.Where (f => f.Attribute ("final")?.Value == "true" && f.Attribute ("value") != null)
 			.ToArray ();
-		var consts = results.Select (f => new Constant {
+		var consts = results.Select (f => new ConstantCandidate {
 			Package = f.Parent.Parent.Attribute ("name").Value,
 			ParentType = f.Parent.Attribute ("name").Value,
+			IsFinal = f.Attribute ("final")?.Value == "true",
 			IsTypeInterface = f.Parent.Name.LocalName == "interface",
 			Name = f.Attribute ("name").Value,
 			FieldType = f.Attribute ("type").Value,
-			Value = f.Attribute ("value").Value,
+			Value = f.Attribute ("value")?.Value,
 			Level = levels [f.Document.BaseUri] 
 			})
 			.OrderBy (c => c.Package)
@@ -52,9 +53,14 @@ public static void Main (string [] args)
 			while (consts [i - x].Name == consts [i].Name && consts [i - x].ParentType == consts [i].ParentType && consts [i - x].Package == consts [i].Package && consts [i - x].Value != consts [i].Value) {
 				Console.Error.WriteLine ("Overwrite field value: {0}.{1}.{2}: {3} (at {4}) -> {5} (at {6})", consts [i - x].Package, consts [i - x].ParentType, consts [i - x].Name, consts [i - x].Value, consts [i - x].Level, consts [i].Value, consts [i].Level);
 				consts [i - x].Value = consts [i].Value;
+				if (!consts [i - x].IsFinal)
+					Console.Error.WriteLine ("Field {0}.{1}.{2} was not constant at API Level {3}", consts [i - x].Package, consts [i - x].ParentType, consts [i - x].Name, consts [i - x].Level);
+				consts [i - x].IsFinal = consts [i].IsFinal;
 				x++;
 			}
 		}
+		
+		consts = consts.Where (f => f.IsFinal).ToArray ();
 
 		var fields = new List<string> ();
 		string package = null, type = null;

src/Mono.Android/map.csv

@@ -1,3 +1,6 @@
+// This file is almost automatically generated by build-tools/enumification-helpers.
+// See README.md there for details.
+
 // this cannot be automatically generated, too exceptional...
 1,Android.Media.Stream,NotificationDefault,android/app/Notification.STREAM_DEFAULT,-1
 1,Android.Media.Stream,Alarm,android/media/AudioManager.STREAM_ALARM,4
@@ -2907,10 +2910,10 @@
 10,Android.Views.Animations.DelayOrder,Normal,android/view/animation/LayoutAnimationController.ORDER_NORMAL,0
 10,Android.Views.Animations.DelayOrder,Random,android/view/animation/LayoutAnimationController.ORDER_RANDOM,2
 10,Android.Views.Animations.DelayOrder,Reverse,android/view/animation/LayoutAnimationController.ORDER_REVERSE,1
-19,Android.Views.Animations.TransformationTypes,Alpha,android/view/animation/Transformation.TYPE_ALPHA,1
-19,Android.Views.Animations.TransformationTypes,Both,android/view/animation/Transformation.TYPE_BOTH,3
-19,Android.Views.Animations.TransformationTypes,Identity,android/view/animation/Transformation.TYPE_IDENTITY,0
-19,Android.Views.Animations.TransformationTypes,Matrix,android/view/animation/Transformation.TYPE_MATRIX,2
+10,Android.Views.Animations.TransformationTypes,Alpha,android/view/animation/Transformation.TYPE_ALPHA,1
+10,Android.Views.Animations.TransformationTypes,Both,android/view/animation/Transformation.TYPE_BOTH,3
+10,Android.Views.Animations.TransformationTypes,Identity,android/view/animation/Transformation.TYPE_IDENTITY,0
+10,Android.Views.Animations.TransformationTypes,Matrix,android/view/animation/Transformation.TYPE_MATRIX,2
 10,Android.Views.InputMethods.ImeAction,ImeMaskAction,android/view/inputmethod/EditorInfo.IME_MASK_ACTION,255
 10,Android.Views.InputMethods.ImeAction,ImeNull,android/view/inputmethod/EditorInfo.IME_NULL,0
 10,Android.Views.InputMethods.ImeAction,Done,android/view/inputmethod/EditorInfo.IME_ACTION_DONE,6
@@ -4532,6 +4535,7 @@
 23,Android.Util.DisplayMetricsDensity,D420,android/util/DisplayMetrics.DENSITY_420,420
 21,Android.Util.DisplayMetricsDensity,D560,android/util/DisplayMetrics.DENSITY_560,560
 10,Android.Util.DisplayMetricsDensity,Default,android/util/DisplayMetrics.DENSITY_DEFAULT,160
+24,Android.Util.DisplayMetricsDensity,DeviceStable,android/util/DisplayMetrics.DENSITY_DEVICE_STABLE,
 10,Android.Util.DisplayMetricsDensity,High,android/util/DisplayMetrics.DENSITY_HIGH,240
 10,Android.Util.DisplayMetricsDensity,Low,android/util/DisplayMetrics.DENSITY_LOW,120
 10,Android.Util.DisplayMetricsDensity,Medium,android/util/DisplayMetrics.DENSITY_MEDIUM,160