[PTZ] Simplify fitness distances for PTZ constrainable properties

This changes pan, tilt and zoom constrainable properties so that for
each them there is a single constrainable property which can be
constrained either with a boolean constraint (resulting in a fitness
distance of 0 or 1) or with a numeric constraint (resulting in a fitness
distance from 0.0 to 1.0).

Spec:
w3c/mediacapture-image#271
w3c/mediacapture-main#766

Change-Id: Iebb0a4f42c518286cefa6b39b2a42f6dbcd30521
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2814545
Commit-Queue: Guido Urdaneta <[email protected]>
Auto-Submit: Eero Häkkinen <[email protected]>
Reviewed-by: Guido Urdaneta <[email protected]>
Cr-Commit-Position: refs/heads/master@{#872352}

third_party/blink/renderer/modules/mediastream/media_stream_constraints_util_video_device.cc

@@ -65,10 +65,7 @@ double NumericValueFitness(const NumericConstraint& constraint,
 
 // Returns the fitness distance between the ideal value of |constraint| and the
 // closest value to it in the range [min, max] if the constraint is supported.
-// If the constraint is present but not supported, returns 1 if there is no
-// ideal value (to account the failed boolean capability constraint) or 2
-// otherwise (to account the failed boolean capability constraint and failed
-// numeric ideal value constraint).
+// If the constraint is present but not supported, returns 1.
 // If the ideal value is contained in the range, returns 0.
 // If there is no ideal value, returns 0;
 // Based on https://w3c.github.io/mediacapture-main/#dfn-fitness-distance.
@@ -81,7 +78,7 @@ double NumericRangeSupportFitness(
   DCHECK(!range.IsEmpty());
 
   if (constraint_present && !constraint_supported)
-    return 1.0 + (constraint.HasIdeal() ? 1.0 : 0.0);
+    return 1.0;
 
   if (!constraint.HasIdeal())
     return 0.0;