Implemented ForceMaximizeBrowserWindowOnFirstRun policy, added unit test and browser test.

ash/shell_delegate.h

Index: ash/shell_delegate.h
diff --git a/ash/shell_delegate.h b/ash/shell_delegate.h
index 148f6867ca331a981be886ccc024a4bbb85e5ff4..a1810acbdadf80b6c311f3315cffe95b26b6e456 100644
--- a/ash/shell_delegate.h
+++ b/ash/shell_delegate.h
@@ -83,6 +83,9 @@ class ASH_EXPORT ShellDelegate {
   // Returns true if multi account is enabled.
   virtual bool IsMultiAccountEnabled() const = 0;
 
+  // Returns true if window must be maximized at the first run.

[bartfab (slow), 2015/03/12 11:54:43]

Nit: You should make it explicit that this applies to the very first window ever
shown only. How about:

"Returns true if the first window shown on first run should be unconditionally
maximized, overriding the heuristic that normally chooses the window size.

[peletskyi, 2015/03/18 13:28:09]

Done.

+  virtual bool IsFirstTimeMaximized() const = 0;

[bartfab (slow), 2015/03/12 11:54:43]

Nit: How about ForceMaximizeOnFirstRun()?

[peletskyi, 2015/03/18 13:28:09]

Done.

+
   // Called before processing |Shell::Init()| so that the delegate
   // can perform tasks necessary before the shell is initialized.
   virtual void PreInit() = 0;