Update changelog for event changes in dart:html

CHANGELOG.md

 ## 1.17.0
 
 ### Core library changes
 * `dart:core`
   * `Uri.replace` supports iterables as values for the query parameters.
   * `Uri.parseIPv6Address` returns a `Uint8List`.
 
 ## 1.16.0
 
 ### Core library changes
 
 * `dart:convert`
   * Added `BASE64URL` codec and corresponding `Base64Codec.urlSafe` constructor.
 
   * Introduce `ChunkedConverter` and deprecate chunked methods on `Converter`.
 
+* `dart:html`
+
+  There have been a number of **BREAKING** changes to align APIs with recent changes Chrome.

[Alan Knight, 2016/04/25 17:09:09]

"in Chrome"

Also line length

[kevmoo, 2016/04/25 21:31:10]

Done.

+  These including:

[Alan Knight, 2016/04/25 17:09:09]

include:

[kevmoo, 2016/04/25 21:31:10]

Done.

+
+  * The `clipboardData` property has been removed from `KeyEvent`
+    and `Event`. It has been moved to the new `ClipboardEvent` class, which is
+    now used by `copy`, `cut`, and `paste` events.
+
+  * The `layer` property has been removed from `KeyEvent` and
+    `UIEvent`. It has been moved to `MouseEvent`.
+
+  * The `Point get page` property has been removed from `UIEvent`.
+    It still exists on `MouseEvent` and `Touch`.
+
+  There have also been a number of other additions and removals to `dart:html`,
+  `dart:indexed_db`, `dart:svg`, `dart:web_audio`, and `dart:web_gl` that
+  correspond to changes to Chrome APIs between v39 and v45. Many of the breaking
+  changes represent APIs that would have caused runtime exceptions when compiled
+  to Javascript and run on recent Chrome releases. 
+

[terry, 2016/04/25 17:56:11]

You'll want to add these too:

1. Chrome's ShadowRoot interface no longer has the method
getElementsByClassName, e.g.,

  getElementsByClassName('clazz')

should become:

  querySelectorAll('.clazz')


2. Mention the @JS() syntax required at the library directive (if the library
has any @JS annotations).

Here's the email I sent out when the change was made.

However, 1.16 will expose a change in how JS Interop is used.  For performance
reasons, an additional requirement is needed to use JS Interop.  Any Dart file
that uses @JS annotations on declarations (top-level functions, classes or class
members) to interop with Javascript code will require that the file have the
annotation @JS() on a ibrary directive  e.g.,

@JS()
library my_library;

The analyzer will enforce this by generating the error:

The @JS() annotation can only be used if it is also declared on the library
directive.

If a file that is a part of a library the library that uses the part should have
the @JS() annotation e.g.,

library_1.dart

@JS()
library library_1;

import 'package:js/js.dart';

part 'part_1.dart';

part_1.dart

part of library_1;

@JS("frameworkStabilizers")
external List<FrameworkStabilizer> get frameworkStabilizers;

If a main Dart file uses interop e.g.

import 'package:js/js.dart';

@JS()
external Function get doubleValue;

main() {
 ...
}

Then at the top you this Dart file/script add following lines (name used for
library can be any valid name):

@JS()
library main1;

If your library already has a JS module e.g.,

@JS('array.utils')
library my_library;

Then your library will work without any additional changes, the @JS annotation
exist.

[kevmoo, 2016/04/25 21:31:10]

Done.

 * `dart:io`
   * Added `SecurityContext.alpnSupported`, which is true if a platform
     supports ALPN, and false otherwise.
 
 ### Analyzer
 
 *   Static checking of `for in` statements. These will now produce static
     warnings:
 
     ```dart
@@ skipping 871 matching lines @@
     they will keep the Dart process alive until they time out. This fixes the
     handling of persistent connections. Previously, the client would shut down
     immediately after a request.
 
   * **Breaking change:** `HttpServer` no longer compresses all traffic by
     default. The new `autoCompress` property can be set to `true` to re-enable
     compression.
 
 * `dart:isolate`: `Isolate.spawnUri` added the optional `packageRoot` argument,
   which controls how it resolves `package:` URIs.