[cssom-view] Editorial: link more instances of "CSS pixel"

Fixes w3c#1214.

Author: zcorpan

cssom-view/Overview.bs

@@ -627,12 +627,12 @@ user agent must run these steps:
 
 The <dfn attribute for=Window>screenX</dfn> attribute must return the x-coordinate,
 relative to the origin of the <a>Web-exposed screen area</a>, of the left of
-the client window as number of pixels, or zero if there is no such
+the client window as number of <a lt=px value>CSS pixels</a>, or zero if there is no such
 thing. <!--fingerprint-->
 
 The <dfn attribute for=Window>screenY</dfn> attribute must return the y-coordinate,
 relative to the origin of the screen of the <a>Web-exposed screen area</a>, of the top of
-the client window as number of pixels, or zero if there is no such
+the client window as number of <a lt=px value>CSS pixels</a>, or zero if there is no such
 thing. <!--fingerprint-->
 
 The <dfn attribute for=Window>outerWidth</dfn> attribute must return the width of the
@@ -692,8 +692,8 @@ To <dfn export>set up browsing context features</dfn> for a browsing context <va
         1. Optionally, clamp <var>width</var> in a user-agent-defined manner so that the window does
             not get too small or bigger than the <a>Web-exposed available screen area</a>.
         1. Optionally, size <var>target</var>'s window by moving its right edge such that the
-            distance between the left and right edges of the viewport are <var>width</var> CSS
-            pixels of <var>target</var>.
+            distance between the left and right edges of the viewport are <var>width</var>
+            <a lt=px value>CSS pixels</a> of <var>target</var>.
         1. Optionally, move <var>target</var>'s window in a user-agent-defined manner so that it
             does not grow outside the <a>Web-exposed available screen area</a>.
 1. If <var>tokenizedFeatures</var>["<a for="supported open() feature name">height</a>"]
@@ -705,8 +705,8 @@ To <dfn export>set up browsing context features</dfn> for a browsing context <va
         1. Optionally, clamp <var>height</var> in a user-agent-defined manner so that the window
             does not get too small or bigger than the <a>Web-exposed available screen area</a>.
         1. Optionally, size <var>target</var>'s window by moving its bottom edge such that the
-            distance between the top and bottom edges of the viewport are <var>height</var> CSS
-            pixels of <var>target</var>.
+            distance between the top and bottom edges of the viewport are <var>height</var>
+            <a lt=px value>CSS pixels</a> of <var>target</var>.
         1. Optionally, move <var>target</var>'s window in a user-agent-defined manner so that it
             does not grow outside the <a>Web-exposed available screen area</a>.