putImageData: Clarify that the operation is not a memcpy

Ensure that it be clear that putImage will convert from the source
ImageData's color space and pixel format to the output bitmap's color
space and pixel format.

Also document the two separate putImageData methods as separate methods
with a common algorithm, rather than a single method with optional
parameters.

source

@@ -65536,7 +65536,7 @@ interface mixin <dfn interface>CanvasImageData</dfn> {
   <span>ImageData</span> <span data-x="dom-context-2d-createImageData">createImageData</span>([EnforceRange] long sw, [EnforceRange] long sh, optional <span>ImageDataSettings</span> settings = {});
   <span>ImageData</span> <span data-x="dom-context-2d-createImageData-imagedata">createImageData</span>(<span>ImageData</span> imagedata);
   <span>ImageData</span> <span data-x="dom-context-2d-getImageData">getImageData</span>([EnforceRange] long sx, [EnforceRange] long sy, [EnforceRange] long sw, [EnforceRange] long sh, optional <span>ImageDataSettings</span> settings = {});
-  undefined <span data-x="dom-context-2d-putImageData">putImageData</span>(<span>ImageData</span> imagedata, [EnforceRange] long dx, [EnforceRange] long dy);
+  undefined <span data-x="dom-context-2d-putImageData-short">putImageData</span>(<span>ImageData</span> imagedata, [EnforceRange] long dx, [EnforceRange] long dy);
   undefined <span data-x="dom-context-2d-putImageData">putImageData</span>(<span>ImageData</span> imagedata, [EnforceRange] long dx, [EnforceRange] long dy, [EnforceRange] long dirtyX, [EnforceRange] long dirtyY, [EnforceRange] long dirtyWidth, [EnforceRange] long dirtyHeight);
 };
 
@@ -70232,16 +70232,33 @@ try {
   component.</p>
 
   <p>The <dfn method for="CanvasImageData"><code
-  data-x="dom-context-2d-putImageData">putImageData()</code></dfn> method writes data from
-  <code>ImageData</code> structures back to the rendering context's <span>output bitmap</span>. Its
-  arguments are: <var>imagedata</var>, <var>dx</var>, <var>dy</var>, <var>dirtyX</var>,
-  <var>dirtyY</var>, <var>dirtyWidth</var>, and <var>dirtyHeight</var>.</p>
+  data-x="dom-context-2d-putImageData-short">putImageData(<var>imagedata</var>,
+  <var>dx</var>, <var>dy</var>)</code></dfn> method will
+  <span data-x="dom-context2d-putImageData-common">put pixels from an
+  <code>ImageData</code> onto an <span>output bitmap</span></span>
+  with <var>bitmap</var> set to the output bitmap of the rendering context,
+  <var>dirtyX</var> and <var>dirtyY</var> set to zero,
+  <var>dirtyWidth</var> and <var>dirtyHeight</var> set to  the
+  <code data-x="dom-imagedata-width">width</code> and
+  <code data-x="dom-imagedata-width">height</code> members
+  of the <var>imagedata</var> structure respectively, and
+  <var>imagedata</var>, <var>dx</var>, and <var>dy</var>
+  as specified.</p>
 
-  <p>When the last four arguments to this method are omitted, they must be assumed to have the
-  values 0, 0, the <code data-x="dom-imagedata-width">width</code> member of the <var>imagedata</var> structure, and the <code data-x="dom-imagedata-height">height</code>
-  member of the <var>imagedata</var> structure, respectively.</p>
+  <p>The <dfn method for="CanvasImageData"><code
+  data-x="dom-context-2d-putImageData">putImageData(<var>imagedata</var>,
+  <var>dx</var>, <var>dy</var>, <var>dirtyX</var>, <var>dirtyY</var>,
+  <var>dirtyWidth</var>, <var>dirtyHeight</var>)</code></dfn> method will
+  <span data-x="dom-context2d-putImageData-common">put pixels from an
+  <code>ImageData</code> onto an <span>output bitmap</span></span>
+  with <var>bitmap</var> set to the output bitmap of the rendering context, and
+  <var>imagedata</var>, <var>dx</var>, <var>dy</var>, <var>dirtyX</var>, <var>dirtyY</var>, <var>dirtyWidth</var>, and <var>dirtyHeight</var>
+  as specified.</p>
 
-  <p>The method, when invoked, must act as follows:</p>
+  <p>To <dfn data-x="dom-context2d-putImageData-common">put pixels from an <code>ImageData</code>
+  onto an output bitmap</dfn>, given an <code>ImageData</code> <var>imagedata</var>,
+  an <span>output bitmap</span> <var>bitmap</var>, and numbers <var>dx</var>, <var>dy</var>,
+  <var>dirtyX</var>, <var>dirtyY</var>, <var>dirthyWidth</var>, and <var>dirthyHeight</var>:</p>
 
   <ol>
    <li><p>Let <var>buffer</var> be <var>imagedata</var>'s <code
@@ -70290,12 +70307,14 @@ try {
    data-x=""><var>dirtyX</var>&nbsp;&le;&nbsp;<var>x</var>&nbsp;&lt;&nbsp;<span
    data-x=""><var>dirtyX</var>+<var>dirtyWidth</var></span></span> and <span
    data-x=""><var>dirtyY</var>&nbsp;&le;&nbsp;<var>y</var>&nbsp;&lt;&nbsp;<span
-   data-x=""><var>dirtyY</var>+<var>dirtyHeight</var></span></span>, copy the
-   four channels of the pixel with coordinate (<var>x</var>, <var>y</var>) in
-   the <var>imagedata</var> data structure's <span>Canvas Pixel
-   <code data-x="idl-ArrayBuffer">ArrayBuffer</code></span> to the pixel with coordinate (<span
-   data-x=""><var>dx</var>+<var>x</var></span>, <var>dy</var>+<var>y</var>)
-   in the rendering context's <span>output bitmap</span>.</p></li>
+   data-x=""><var>dirtyY</var>+<var>dirtyHeight</var></span></span>,
+   set the pixel with coordinate (<span data-x=""><var>dx</var>+<var>x</var></span>,
+   <var>dy</var>+<var>y</var>) in <var>bitmap</var> to the color at coordinate
+   (<var>x</var>, <var>y</var>) in the <var>imagedata</var> data structure's
+   <span>Canvas Pixel <code data-x="idl-ArrayBuffer">ArrayBuffer</code></span>,
+   converted from <var>imageData</var>'s <code data-x="dom-imagedata-colorSpace">colorSpace</code>
+   to the <span data-x="concept-canvas-color-space">color space</span> of <var>bitmap</var>
+   using <span>'relative-colorimetric'</span> rendering intent.</p></li>
   </ol>
 
   <p class="note">Due to the lossy nature of converting between color spaces and converting to and