Don't expose page zoom in screenPixelRatio

This ensures it is updated with the spec defined in
https://w3c.github.io/mediacapture-screen-share/#dfn-screenpixelratio.
This CL also renames pixelRatio to screenPixelRatio as it is called in
the spec.

Bug: 396746625
Change-Id: I3ed1b0c3f2212d86207ce6167d227230781d7fcb
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6405674
Reviewed-by: Guido Urdaneta <[email protected]>
Commit-Queue: Guido Urdaneta <[email protected]>
Cr-Commit-Position: refs/heads/main@{#1439690}

Author: palak8669

screen-capture/tentative/getdisplaymedia-captured-surface-resolution.https.html

@@ -39,7 +39,7 @@
       assert_greater_than(settings.physicalHeight, 0);
       assert_equals(settings.physicalWidth / screenDetails.screens[0].devicePixelRatio, settings.logicalWidth);
       assert_equals(settings.physicalHeight / screenDetails.screens[0].devicePixelRatio, settings.logicalHeight);
-      assert_equals(screenDetails.screens[0].devicePixelRatio, settings.pixelRatio);
+      assert_equals(screenDetails.screens[0].devicePixelRatio, settings.screenPixelRatio);
       assert_equals(capabilities.width.max, settings.physicalWidth);
       assert_equals(capabilities.height.max, settings.physicalHeight);
     };
@@ -64,7 +64,7 @@
       assert_greater_than(settings.physicalHeight, 0);
       assert_equals(settings.physicalWidth / screenDetails.screens[0].devicePixelRatio, settings.logicalWidth);
       assert_equals(settings.physicalHeight / screenDetails.screens[0].devicePixelRatio, settings.logicalHeight);
-      assert_equals(screenDetails.screens[0].devicePixelRatio, settings.pixelRatio);
+      assert_equals(screenDetails.screens[0].devicePixelRatio, settings.screenPixelRatio);
       assert_equals(capabilities.width.max, settings.physicalWidth);
       assert_equals(capabilities.height.max, settings.physicalHeight);
     };
@@ -87,7 +87,7 @@
       assert_greater_than(settings.physicalHeight, 0);
       assert_equals(settings.physicalWidth / window.devicePixelRatio, settings.logicalWidth);
       assert_equals(settings.physicalHeight / window.devicePixelRatio, settings.logicalHeight);
-      assert_equals(window.devicePixelRatio, settings.pixelRatio);
+      assert_equals(window.devicePixelRatio, settings.screenPixelRatio);
       assert_equals(capabilities.width.max, settings.physicalWidth);
       assert_equals(capabilities.height.max, settings.physicalHeight);
     };
@@ -123,7 +123,7 @@
       assert_equals(oldPhysicalHeight, settings.physicalHeight);
       assert_equals(oldPhysicalWidth / screenDetails.screens[0].devicePixelRatio, settings.logicalWidth);
       assert_equals(oldPhysicalHeight / screenDetails.screens[0].devicePixelRatio, settings.logicalHeight);
-      assert_equals(screenDetails.screens[0].devicePixelRatio, settings.pixelRatio);
+      assert_equals(screenDetails.screens[0].devicePixelRatio, settings.screenPixelRatio);
       assert_equals(capabilities.width.max, settings.physicalWidth);
       assert_equals(capabilities.height.max, settings.physicalHeight);
     };
@@ -159,7 +159,7 @@
       assert_equals(oldPhysicalHeight, settings.physicalHeight);
       assert_equals(oldPhysicalWidth / screenDetails.screens[0].devicePixelRatio, settings.logicalWidth);
       assert_equals(oldPhysicalHeight / screenDetails.screens[0].devicePixelRatio, settings.logicalHeight);
-      assert_equals(screenDetails.screens[0].devicePixelRatio, settings.pixelRatio);
+      assert_equals(screenDetails.screens[0].devicePixelRatio, settings.screenPixelRatio);
       assert_equals(capabilities.width.max, settings.physicalWidth);
       assert_equals(capabilities.height.max, settings.physicalHeight);
     };
@@ -193,7 +193,7 @@
       assert_equals(oldPhysicalHeight, settings.physicalHeight);
       assert_equals(oldPhysicalWidth / window.devicePixelRatio, settings.logicalWidth);
       assert_equals(oldPhysicalHeight / window.devicePixelRatio, settings.logicalHeight);
-      assert_equals(window.devicePixelRatio, settings.pixelRatio);
+      assert_equals(window.devicePixelRatio, settings.screenPixelRatio);
       assert_equals(capabilities.width.max, settings.physicalWidth);
       assert_equals(capabilities.height.max, settings.physicalHeight);
     };