[cssom-view] Fix grammar "all descendant boxes"

Fixes https://www.w3.org/Bugs/Public/show_bug.cgi?id=29319.

Author: zcorpan

cssom-view/Overview.bs

@@ -170,11 +170,11 @@ The term <dfn>scrolling area</dfn> refers to a box of a <a>viewport</a> or an el
      <dt>top edge
      <dd>The top edge of the <a>initial containing block</a>.
      <dt>right edge
-     <dd>The right-most edge of the right edge of the <a>initial containing block</a> and the right <a>margin edge</a> of the
-     <a>viewport’s</a> all descendant boxes.
+     <dd>The right-most edge of the right edge of the <a>initial containing block</a> and the right
+     <a>margin edge</a> of all of the <a>viewport’s</a> descendants' boxes.
      <dt>bottom edge
-     <dd>The bottom-most edge of the bottom edge of the <a>initial containing block</a> and the bottom <a>margin edge</a> of the
-     <a>viewport’s</a> all descendant boxes.
+     <dd>The bottom-most edge of the bottom edge of the <a>initial containing block</a> and the
+     bottom <a>margin edge</a> of all of the <a>viewport’s</a> descendants' boxes.
      <dt>left edge
      <dd>The left edge of the <a>initial containing block</a>.
     </dl>
@@ -183,10 +183,12 @@ The term <dfn>scrolling area</dfn> refers to a box of a <a>viewport</a> or an el
      <dt>top edge
      <dd>The element's top <a>padding edge</a>.
      <dt>right edge
-     <dd>The right-most edge of the element's right <a>padding edge</a> and the right <a>margin edge</a> of the element's all descendant boxes,
+     <dd>The right-most edge of the element's right <a>padding edge</a> and the right <a>margin
+     edge</a> of all of the element's descendants' boxes,
      excluding boxes that have an ancestor of the element as their containing block.
      <dt>bottom edge
-     <dd>The bottom-most edge of the element's bottom <a>padding edge</a> and the bottom <a>margin edge</a> of the element's all descendant
+     <dd>The bottom-most edge of the element's bottom <a>padding edge</a> and the bottom <a>margin
+     edge</a> of all of the element's descendants'
      boxes, excluding boxes that have an ancestor of the element as their containing block.
      <dt>left edge
      <dd>The element's left <a>padding edge</a>.
@@ -200,11 +202,11 @@ The term <dfn>scrolling area</dfn> refers to a box of a <a>viewport</a> or an el
      <dt>right edge
      <dd>The right edge of the <a>initial containing block</a>.
      <dt>bottom edge
-     <dd>The bottom-most edge of the bottom edge of the <a>initial containing block</a> and the bottom <a>margin edge</a> of the
-     <a>viewport’s</a> all descendant boxes.
+     <dd>The bottom-most edge of the bottom edge of the <a>initial containing block</a> and the
+     bottom <a>margin edge</a> of all of the <a>viewport’s</a> descendants' boxes.
      <dt>left edge
-     <dd>The left-most edge of the left edge of the <a>initial containing block</a> and the left <a>margin edge</a> of the
-     <a>viewport’s</a> all descendant boxes.
+     <dd>The left-most edge of the left edge of the <a>initial containing block</a> and the left
+     <a>margin edge</a> of all of the <a>viewport’s</a> descendants' boxes.
     </dl>
    <td class=long>
     <dl>
@@ -213,50 +215,54 @@ The term <dfn>scrolling area</dfn> refers to a box of a <a>viewport</a> or an el
      <dt>right edge
      <dd>The element's right <a>padding edge</a>.
      <dt>bottom edge
-     <dd>The bottom-most edge of the element's bottom <a>padding edge</a> and the bottom <a>margin edge</a> of the element's all descendant
-     boxes, excluding boxes that have an ancestor of the element as their containing block.
+     <dd>The bottom-most edge of the element's bottom <a>padding edge</a> and the bottom <a>margin
+     edge</a> of all of the element's descendants' boxes, excluding boxes that have an ancestor of
+     the element as their containing block.
      <dt>left edge
-     <dd>The left-most edge of the element's left <a>padding edge</a> and the left <a>margin edge</a> of the element's all descendant boxes,
-     excluding boxes that have an ancestor of the element as their containing block.
+     <dd>The left-most edge of the element's left <a>padding edge</a> and the left <a>margin
+     edge</a> of all of the element's descendants' boxes, excluding boxes that have an ancestor of
+     the element as their containing block.
     </dl>
   <tr>
    <td>leftward and upward
    <td class=long>
     <dl>
      <dt>top edge
-     <dd>The top-most edge of the top edge of the <a>initial containing block</a> and the top <a>margin edge</a> of the
-     <a>viewport’s</a> all descendant boxes.
+     <dd>The top-most edge of the top edge of the <a>initial containing block</a> and the top
+     <a>margin edge</a> of all of the <a>viewport’s</a> descendants' boxes.
      <dt>right edge
      <dd>The right edge of the <a>initial containing block</a>.
      <dt>bottom edge
      <dd>The bottom edge of the <a>initial containing block</a>.
      <dt>left edge
-     <dd>The left-most edge of the left edge of the <a>initial containing block</a> and the left <a>margin edge</a> of the
-     <a>viewport’s</a> all descendant boxes.
+     <dd>The left-most edge of the left edge of the <a>initial containing block</a> and the left
+     <a>margin edge</a> of all of the <a>viewport’s</a> descendants' boxes.
     </dl>
    <td class=long>
     <dl>
      <dt>top edge
-     <dd>The top-most edge of the element's top <a>padding edge</a> and the top <a>margin edge</a> of the element's all descendant boxes,
-     excluding boxes that have an ancestor of the element as their containing block.
+     <dd>The top-most edge of the element's top <a>padding edge</a> and the top <a>margin edge</a>
+     of all of the element's descendants' boxes, excluding boxes that have an ancestor of the
+     element as their containing block.
      <dt>right edge
      <dd>The element's right <a>padding edge</a>.
      <dt>bottom edge
      <dd>The element's bottom <a>padding edge</a>.
      <dt>left edge
-     <dd>The left-most edge of the element's left <a>padding edge</a> and the left <a>margin edge</a> of the element's all descendant boxes,
-     excluding boxes that have an ancestor of the element as their containing block.
+     <dd>The left-most edge of the element's left <a>padding edge</a> and the left <a>margin
+     edge</a> of all of the element's descendants' boxes, excluding boxes that have an ancestor of
+     the element as their containing block.
     </dl>
   <tr>
    <td>rightward and upward
    <td class=long>
     <dl>
      <dt>top edge
-     <dd>The top-most edge of the top edge of the <a>initial containing block</a> and the top <a>margin edge</a> of the
-     <a>viewport’s</a> all descendant boxes.
+     <dd>The top-most edge of the top edge of the <a>initial containing block</a> and the top
+     <a>margin edge</a> of all of the <a>viewport’s</a> descendants' boxes.
      <dt>right edge
-     <dd>The right-most edge of the right edge of the <a>initial containing block</a> and the right <a>margin edge</a> of the
-     <a>viewport’s</a> all descendant boxes.
+     <dd>The right-most edge of the right edge of the <a>initial containing block</a> and the right
+     <a>margin edge</a> of all of the <a>viewport’s</a> descendants' boxes.
      <dt>bottom edge
      <dd>The bottom edge of the <a>initial containing block</a>.
      <dt>left edge
@@ -265,11 +271,13 @@ The term <dfn>scrolling area</dfn> refers to a box of a <a>viewport</a> or an el
    <td class=long>
     <dl>
      <dt>top edge
-     <dd>The top-most edge of the element's top <a>padding edge</a> and the top <a>margin edge</a> of the element's all descendant boxes,
-     excluding boxes that have an ancestor of the element as their containing block.
+     <dd>The top-most edge of the element's top <a>padding edge</a> and the top <a>margin edge</a>
+     of all of the element's descendants' boxes, excluding boxes that have an ancestor of the
+     element as their containing block.
      <dt>right edge
-     <dd>The right-most edge of the element's right <a>padding edge</a> and the right <a>margin edge</a> of the element's all descendant boxes,
-     excluding boxes that have an ancestor of the element as their containing block.
+     <dd>The right-most edge of the element's right <a>padding edge</a> and the right <a>margin
+     edge</a> of all of the element's descendants' boxes, excluding boxes that have an ancestor of
+     the element as their containing block.
      <dt>bottom edge
      <dd>The element's bottom <a>padding edge</a>.
      <dt>left edge