Docs: Added missing forceContextRestore method.

Author: mrdoob

docs/api/en/renderers/WebGLRenderer.html

@@ -316,11 +316,16 @@ <h3>[method:Object extensions.get]( [param:String extensionName] )</h3>
 		- *WEBGL_compressed_texture_etc1*
 		</p>
 
-		<h3>[method:null forceContextLoss]( )</h3>
+		<h3>[method:void forceContextLoss]()</h3>
 		<p>
 		Simulate loss of the WebGL context. This requires support for the
 			[link:https://developer.mozilla.org/en-US/docs/Web/API/WEBGL_lose_context WEBGL_lose_context] extensions.
-		According to [link:https://webglstats.com/ WebGLStats], as of February 2016 90% of WebGL enabled devices support this.
+		</p>
+
+		<h3>[method:void forceContextRestore]( )</h3>
+		<p>
+		Simulate restore of the WebGL context. This requires support for the
+			[link:https://developer.mozilla.org/en-US/docs/Web/API/WEBGL_lose_context WEBGL_lose_context] extensions.
 		</p>
 
 		<h3>[method:Float getClearAlpha]()</h3>

docs/api/zh/renderers/WebGLRenderer.html

@@ -300,11 +300,16 @@ <h3>[method:Object extensions.get]( [param:String extensionName] )</h3>
 		- *WEBGL_compressed_texture_etc1*
 		</p>
 
-		<h3>[method:null forceContextLoss]( )</h3>
+		<h3>[method:void forceContextLoss]()</h3>
 		<p>
 		模拟WebGL环境的丢失。需要支持
 			[link:https://developer.mozilla.org/en-US/docs/Web/API/WEBGL_lose_context WEBGL_lose_context]扩展才能用。
-		根据[link:https://webglstats.com/ WebGLStats], as of February 2016 90% of WebGL enabled devices support this.
+		</p>
+
+		<h3>[method:void forceContextRestore]( )</h3>
+		<p>
+		Simulate restore of the WebGL context. This requires support for the
+			[link:https://developer.mozilla.org/en-US/docs/Web/API/WEBGL_lose_context WEBGL_lose_context] extensions.
 		</p>
 
 		<h3>[method:Float getClearAlpha]()</h3>