Fix context restore. (#4031)

Fixes missing docs (#3925)

Documents events for DisplayObject, renderers, Texture and BaseTexture (#3922) ...

* Documents events for DisplayObject, renderers, Texture and BaseTexture

* Converts to single-line event syntax

* Adds mouse/touch/pointer events for DisplayObject, fixes typo, adds interactive and interactiveChildren

* Added missing params on touchcancel and pointercancel

* Better helper docs for DisplayObject and Container

* Fix lint

* Removes mixin doc for PIXI.interaction.interactiveTarget

* Added more explicit types for `originalEvent`

* Fixes lint issue

Documentation Updates: namespaces & plugins (#3907) ...

* Better job documenting plugins and namespace

* Fixes linting errors

* Disabling hardwrap because of ESlint

* @readOnly becomes @readonly

* Fixes description, adds link, more info about excluding plugins

* Missed description

* Fixes typos

* Adds missing word

Merge branch 'master' into dev

autoFit temporary fix (#3894) ...

* autoFit temporary fix

* one line

Converts renderer options to object-only, but backward support (#3773)

Little improve: Don't query `currentState` again (#3764)

Fix `the fault after merge` (#3766) ...

* Fix `the fault after merge`

* Remove duplicate comment

* Update Filter.js

* Update Filter.js

Pass `currentState` to filter.apply() (#3421) ...

* Pass ```currentState``` to filter.apply()

see https://github.com/pixijs/pixi.js/issues/3317 

If  pass ```currentState``` to filter.apply() , users could get more informations  (e.g. get current sprite by ```currentSprite = currentState.target```).
It's very useful when users create custom filters.

And the ```currentState``` is the last argument , and pass it won't break any filter already existed.

So I think this PR is safe and useful.

* Update annotation about currentState in Filter.js

* Use eslint-disable-line

* Update FilterManager.js

* Update Filter.js

[v4.4] Revert "Fix #3609 , about `filterClamp` & `filterArea` (#3626)" (#3760) ...

* Revert "Fix #3609 , about `filterClamp` & `filterArea`  (#3626)"

The real fix is to exclude "filterClamp" from uniformData
That fixes outlineFilter and glowFilter

* added a test, so finscn wont break it again ;)

User can decide whether auto-set the projection (#3612) ...

* User can decide whether  auto-set the projection

`bindShader` always  set the projection matrix  automatically . in most case ,  that's OK.

But When I create some new renderer of PIXI ,  sometimes it would make some problems.
e.g.
* shader no projectionMatrix
* shader need use a custom projectionMatrix (not  _activeRenderTarget's)
* shader use a cached array (don't want to call toArray every time)

So I add a new argument to `bindShader` , and the default value is true, so  it would break any current code of PIXI

.

* Update WebGLRenderer.js

Fixed crash in WebGLState::push(). (#3652)

fixed lint warnings (#3726)

Merge branch 'master' into dev

filter slot #0 for textures (#3721)

Add an easy way to clear RenderTexture (#3647) ...

* Add a easy way to clear RenderTexture

In current PIXI, clear a RenderTexture is complex : 
```
renderer.bindRenderTexture(myRenderTexture);
renderer.clear();
// restore the previous renderTexture
renderer.bindRenderTexture();
```
And bind renderTexture is a high-cost operation . We shouldn't call it for cleaning render texture.

So I  add this method.

relatived : https://github.com/pixijs/pixi.js/issues/3595

* Add `return this`

initial commit for ultimate renderer dimensions solution (#3657)

Fix docs and export issue, Filter is a class

Added legacy option to webGL renderer (#3630) ...

* Added legacy option to webGL renderer

Setting ```legacy``` to true now forces VertexArrayObjects and
MultiTexture Batching to be disabled. We also store the variable on the
renderer just incase we want to use it to force settings in anything
else.

also added a test

* remove WebGLTests as they don't work on server

* Added extra param to Application

* Adds WebGL test for legacy

* Better check for WebGL in tests

Better respecting of the scale mode (#3678)

FilterManager shaderCache reset as object (#3664) ...

The shaderCache is initially created as an object. When the Filter Manager gets destroyed, it should be reset to an empty object, not an array.

Fix #3609 , about `filterClamp` & `filterArea` (#3626) ...

* Fix : about filterArea & filterClamp

* Remove needless code

* cosmetice

FilterManager: (#3632) ...

don't clear the entire target buffer when popping the last filter
  fixes issues with applying multiple filters to a single object

Fix resolution setting of PIXI.Filter, and another two wrong codes on resolution importing (#3614) ...

* Fix resolution setting of PIXI.Filter

* fix default value of blur filters' resolution

* fix a bug: use `settings.RESOLUTION` instead of import the constant

added check for root (#3545) ...

* added check for root

* Added note to future us..

fix for invalid texture (#3474) ...

* fix for invalid texture

* new approach to fix

undo last fix
add fix into texture manager

* added break (thanks @finscn)

* fixed little typo

* implemented @englercj tweaks

* on reflection, this should never be null!

fixed some filter issues with textures not clearing correctly (#3525) ...

* fixed some filter issues with textures not clearing correctly

* removed commented code

* added a clear to the correct place (when filters are stacked)

Protect the initial state of `this._activeRenderTarget` in _indexContext (#3443) ...

* Update WebGLRenderer.js

```
    this._activeRenderTarget = null;
    this._activeTextureLocation = 999;
    this._activeTexture = null;
````
must before `this._indexContext()` , otherwise  the _activeRenderTarget & _activeTexture init in  _indexContext will back to `null`.

* Add a blank line for cosmetic.

Do not unload generated textures when manually running the texture garbage collector. This already happens when it is run automatically, as it will cause the texture to not be able to be renderered again (#3342)