Use required Image Capture constraints to overconstrain

Advanced constraints sets passed to the MediaStreamTrack
applyConstraints method should either be applied or discarded
(SelectSettings algorithm[1] step 5.2). They should
never cause an OverconstrainedError to be thrown.

[1]: https://w3c.github.io/mediacapture-main/#dfn-selectsettings

Bug: 1408091
Change-Id: I6b7c4e12ed913917ccfc01796df5f96af5e0bc3f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5625777
Reviewed-by: Rijubrata Bhaumik <[email protected]>
Commit-Queue: Eero Hakkinen <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1315201}

Author: eehakkin

mediacapture-extensions/GUM-backgroundBlur.https.html

@@ -90,9 +90,9 @@ <h1 class="instructions">Description</h1>
     const [videoTrack] = stream.getVideoTracks();
 
     const capabilities = videoTrack.getCapabilities();
-    const constraints = {advanced: [{
-      [property]: constraintSet[property]
-    }]};
+    const constraints = {
+      [property]: {exact: constraintSet[property]}
+    };
     const oldSettings = videoTrack.getSettings();
 
     if (supportedConstraints[property] && !(property in capabilities)) {