docs(dart): cleanup 'live example' links (#1449)

This fixes various issues such as:
- missing space in Dart version between the live demo and demo source
links.
- Live example link directing to Plunker for Dart.

The main mixins (`liveExampleLink`*) used to support the generation of
links now assume reasonable default values for their arguments, and in
most cases the defaults are used.

* Dart example links: use http vs https

As agree to with @kwalrath.

public/docs/dart/latest/_util-fns.jade

@@ -14,12 +14,16 @@ include ../../../_includes/_util-fns
 - var _liveLink = 'sample repo';
 
 mixin liveExampleLink(linkText, exampleUrlPartName)
-  a(href='https://angular-examples.github.io/#{exampleUrlPartName}' target="_blank")= linkText
+  - var text = linkText || 'live example';
+  - var ex = exampleUrlPartName || getExampleName();
+  - var href = 'http://angular-examples.github.io/' + ex;
+  a(href='#{href}' target="_blank")= text
 
 mixin liveExampleLink2(linkText, exampleUrlPartName)
-  - var liveExampleSourceLinkText = attributes.srcLinkText || 'view source'
-  | #[+liveExampleLink(linkText, exampleUrlPartName)]
-  | (#[a(href='https://github.com/angular-examples/#{exampleUrlPartName}' target="_blank") #{liveExampleSourceLinkText}])
+  - var srcText = attributes.srcText || 'view source';
+  - var ex = exampleUrlPartName || attributes.example || getExampleName();
+  - var href = 'http://github.com/angular-examples/' + ex;
+  span #[+liveExampleLink(linkText, ex)] (#[a(href='#{href}' target="_blank") #{srcText}])
 
 - var adjustExamplePath = function(_path) {
 -   if(!_path) return _path;

public/docs/ts/latest/_util-fns.jade

@@ -5,8 +5,11 @@ include ../../../_includes/_util-fns
 //- Other values match the defaults.
 
 mixin liveExampleLink(linkText, exampleUrlPartName)
-  a(href='/resources/live-examples/#{exampleUrlPartName}/ts/plnkr.html' target="_blank")= linkText
+  - var text = linkText || 'live example';
+  - var ex = exampleUrlPartName || getExampleName();
+  - var href = '/resources/live-examples/' + ex + '/ts/plnkr.html';
+  a(href='#{href}' target="_blank")= text
 
 mixin liveExampleLink2(linkText, exampleUrlPartName)
-  //- In Dart this also gives a link to the source.
-  | #[+liveExampleLink(linkText, exampleUrlPartName)]
+  //- In Dart this gives 2 links: to the demo and to the source.
+  +liveExampleLink(linkText, exampleUrlPartName)

public/docs/ts/latest/guide/attribute-directives.jade

@@ -10,8 +10,9 @@ block includes
   * [apply the attribute directive to an element in a template](#apply-directive)
   * [respond to user-initiated events](#respond-to-user)
   * [pass values into the directive using data binding](#bindings)
-p.
-  #[+liveExampleLink2('Live example', 'attribute-directives')].
+
+p Try the #[+liveExampleLink2()].
+
 :marked
   ## Directives overview
   

public/docs/ts/latest/guide/component-styles.jade

@@ -19,9 +19,8 @@ block includes
   * [Controlling View Encapsulation: Emulated, Native, and None](#view-encapsulation)
   * [Appendix 1: Inspecting the generated runtime component styles](#inspect-generated-css)
   * [Appendix 2: Loading Styles with Relative URLs](#relative-urls)
-p
-  | #[+liveExampleLink2('Run the live example', 'component-styles')] 
-  | of the code shown in this chapter.
+
+p Run the #[+liveExampleLink2()] of the code shown in this chapter.
 
 .l-main-section
 :marked

public/docs/ts/latest/guide/hierarchical-dependency-injection.jade

@@ -12,8 +12,8 @@ block includes
   interesting and useful results.
 
   In this chapter we explore these points and write some code.
-p
-  | Try the #[+liveExampleLink2('live example', 'hierarchical-dependency-injection')].
+
+p Try the #[+liveExampleLink2()].
 
 .l-main-section
 :marked

public/docs/ts/latest/guide/lifecycle-hooks.jade

@@ -24,7 +24,7 @@ block includes
     * [AfterViewInit and AfterViewChecked](#afterview)
     * [AfterContentInit and AfterContentChecked](#aftercontent)
 
-p Try the #[+liveExampleLink2('live example', 'lifecycle-hooks')].
+p Try the #[+liveExampleLink2()].
 
 a#hooks-overview
 .l-main-section
@@ -199,7 +199,7 @@ a#the-sample
 .l-main-section
 h2 Lifecycle exercises
 p.  
-  The #[+liveExampleLink('live example', 'lifecycle-hooks')]
+  The #[+liveExampleLink()]
   demonstrates the lifecycle hooks in action through a series of exercises
   presented as components under the control of the root `AppComponent`.
 :marked

public/docs/ts/latest/guide/pipes.jade

@@ -17,7 +17,7 @@ block includes
   In fact, we'd like to apply them in our HTML templates as we do styles.
 p.
   Welcome, Angular pipes, the simple display-value transformations that we can declare in our HTML!
-  Try the #[+liveExampleLink2('live example', 'pipes')].
+  Try the #[+liveExampleLink2()].
 
 .l-main-section
 :marked
@@ -169,7 +169,7 @@ figure.image-display
     Custom pipes must be registered manually.
 
 p.
-  If we try the #[+liveExampleLink('live code', 'pipes')] example,
+  If we try the #[+liveExampleLink()],
   we can probe its behavior by changing the value and the optional exponent in the template.
 
 :marked
@@ -219,10 +219,10 @@ a#change-detection
   Here's the `FlyingHeroesPipe` implementation which follows the pattern for custom pipes we saw earlier.
 +makeExample('pipes/ts/app/flying-heroes.pipe.ts', 'pure', 'app/flying-heroes.pipe.ts')(format='.')
 
-:marked
-  When we run the sample now we see odd behavior (try it in the [live example](/resources/live-examples/pipes/ts/plnkr.html)).
+p.
+  When we run the sample now we see odd behavior (try it in the #[+liveExampleLink()]).
   Every hero we add is a flying hero but none of them are displayed.
-
+:marked
   Although we're not getting the behavior we want, Angular isn't broken.
   It's just using a different change detection algorithm — one that ignores changes to the list or any of its items.
 
@@ -238,7 +238,7 @@ a#change-detection
 
   *If we **mutate** the #{_array}, no pipe is invoked and no display updated;
   if we **replace** the #{_array}, then the pipe executes and the display is updated*.
-  The *Flying Heroes* in the [live example](/resources/live-examples/pipes/ts/plnkr.html) extends the
+  The *Flying Heroes* extends the
   code with checkbox switches and additional displays to help us experience these effects.
 
 figure.image-display
@@ -328,15 +328,15 @@ block pure-change
 
   We can derive a `FlyingHeroesImpureComponent` that we derive from the `FlyingHeroesComponent`.
 +makeExample('pipes/ts/app/flying-heroes.component.ts','impure-component','app/flying-heroes.component.ts (FlyingHeroesImpureComponent)')(format='.')
-:marked
+p.
   The only substantive change is the pipe.
-  We can confirm in the [live example](/resources/live-examples/pipes/ts/plnkr.html)
-  that the *flying heroes* display updates as we enter new heroes even when we mutate the `heroes` #{_array}.
-- var _dollar = _docsFor === 'ts' ? '$' : '';
-:marked
-  <a id="async-pipe"></a>
-  ### The impure *AsyncPipe*
+  We can confirm in the #[+liveExampleLink()] that the #[i flying heroes]
+  display updates as we enter new heroes even when we mutate the
+  #[code heroes] #{_array}.
 
+- var _dollar = _docsFor === 'ts' ? '$' : '';
+h3#async-pipe The impure #[i AsyncPipe]
+:marked
   The Angular `AsyncPipe` is an interesting example of an impure pipe.
   The `AsyncPipe` accepts a `#{_Promise}` or `#{_Observable}` as input
   and subscribes to the input automatically, eventually returning the emitted value(s).

public/docs/ts/latest/guide/server-communication.jade

@@ -36,9 +36,9 @@ ul
       li #[a(href="#search-parameters") Set query string parameters]
       li #[a(href="#more-observables") Debounce search term input]
   li #[a(href="#in-mem-web-api") Appendix: the in-memory web api service]
-p.  
+p.
   We illustrate these topics with code that you can 
-  #[+liveExampleLink2('run live in a browser', 'server-communication')].
+  #[+liveExampleLink2('run live in a browser')].
   
 .l-main-section
 h1 Demos
@@ -694,4 +694,4 @@ block redirect-to-web-api
 p Here is the revised (and final) version of the #[code #[+adjExPath('app/main.ts')]] demonstrating these steps.
 +makeExample('server-communication/ts/app/main.ts', 'final', 'app/main.ts (final)')(format=".")
 
-p See the full source code in the #[+liveExampleLink2('live example', 'server-communication')].
+p See the full source code in the #[+liveExampleLink2()].

public/docs/ts/latest/guide/structural-directives.jade

@@ -14,8 +14,8 @@ block includes
   - [discover the <template> element](#template)
   - [understand the asterisk (\*) in **ngFor*](#asterisk)
   - [write our own structural directive](#unless)
-p
-  | Try the #[+liveExampleLink2('live example', 'structural-directives')].
+
+p Try the #[+liveExampleLink2()].
 
 <a id="definition"></a>
 .l-main-section

public/docs/ts/latest/quickstart.jade

@@ -22,7 +22,7 @@ block includes
 
 h1 Try it!
 p
-  | Try the #[+liveExampleLink2('live example', 'quickstart')] which loads the sample app
+  | Try the #[+liveExampleLink2()] which loads the sample app
   +ifDocsFor('ts')
     |  in #[a(href="http://plnkr.co/" title="Plunker" target="_blank") plunker]
   |  and displays the simple message: