Maximize browser window before running the tests

By the default the browser window is not maximized, but opened with a
size of 1050x978px. In the Files app, when the navigation bar and the
side bar are both open, with the previous design that width caused the
file name to be very very narrow, but still clickable. However, with the
updated design the file name is too narrow and no longer clickable,
which breaks several acceptance tests that descend into subfolders. To
solve that now the browser window is maximized before running the tests,
which makes the window wide enough (1360px) to show the file name and
make it clickable.

This commit also removes a step to close the sidebar that was recently
added to address the problem mentioned above in a previous pull request.

Signed-off-by: Daniel Calviño Sánchez <danxuliu@gmail.com>

tests/acceptance/features/app-files-sharing-link.feature

@@ -119,7 +119,6 @@ Feature: app-files-sharing-link
     And I create a new folder named "Subfolder"
     And I see that the file list contains a file named "Subfolder"
     When I act as John
-    And I close the details view
     And I enter in the folder named "Editable shared folder"
     Then I see that the file list contains a file named "Subfolder"
 

tests/acceptance/features/core/ActorContext.php

@@ -137,6 +137,8 @@ class ActorContext extends RawMinkContext {
 
 		$this->getSession()->start();
 
+		$this->getSession()->maximizeWindow();
+
 		$this->actors["default"] = new Actor("default", $this->getSession(), $this->getMinkParameter("base_url"), $this->sharedNotebook);
 		$this->actors["default"]->setFindTimeoutMultiplier($this->actorTimeoutMultiplier);
 
@@ -163,6 +165,8 @@ class ActorContext extends RawMinkContext {
 		if (!array_key_exists($actorName, $this->actors)) {
 			$this->getSession($actorName)->start();
 
+			$this->getSession($actorName)->maximizeWindow();
+
 			$this->actors[$actorName] = new Actor($actorName, $this->getSession($actorName), $this->getMinkParameter("base_url"), $this->sharedNotebook);
 			$this->actors[$actorName]->setFindTimeoutMultiplier($this->actorTimeoutMultiplier);
 		}