Remove docked windows entirely in M59.

components/sessions/core/session_service_commands.cc

Index: components/sessions/core/session_service_commands.cc
diff --git a/components/sessions/core/session_service_commands.cc b/components/sessions/core/session_service_commands.cc
index d066372deaa837d96429fe52a5c52c4d523599aa..b417f95606bdbc925495c322cee552ee223b5579 100644
--- a/components/sessions/core/session_service_commands.cc
+++ b/components/sessions/core/session_service_commands.cc
@@ -113,8 +113,7 @@ enum PersistedWindowShowState {
   // SHOW_STATE_INACTIVE (4) never persisted.
   PERSISTED_SHOW_STATE_FULLSCREEN = 5,
   PERSISTED_SHOW_STATE_DETACHED_DEPRECATED = 6,
-  PERSISTED_SHOW_STATE_DOCKED_DEPRECATED = 7,
-  PERSISTED_SHOW_STATE_END = 7
+  PERSISTED_SHOW_STATE_END = 6

[varkha, 2017/02/28 00:59:03]

I don't think you can remove DOCKED_DEPRECATED here without breaking the profile
history. You can remove the handling of docked state in
ShowStateToPersistedShowState() (since no window will ever be docked) but I
think you need to leave the handler for the deprecated state in
PersistedShowStateToShowState() and simply return ui:SHOW_STATE_NORMAL there in
old line 171.

[afakhry, 2017/03/09 22:28:27]

Done.

 };
 
 using IdToSessionTab =
@@ -140,11 +139,6 @@ PersistedWindowShowState ShowStateToPersistedShowState(
       return PERSISTED_SHOW_STATE_MAXIMIZED;
     case ui::SHOW_STATE_FULLSCREEN:
       return PERSISTED_SHOW_STATE_FULLSCREEN;
-
-    // TODO(afakhry): Remove Docked Windows in M58.
-    case ui::SHOW_STATE_DOCKED:
-      return PERSISTED_SHOW_STATE_DOCKED_DEPRECATED;
-
     case ui::SHOW_STATE_DEFAULT:
     case ui::SHOW_STATE_INACTIVE:
       return PERSISTED_SHOW_STATE_NORMAL;
@@ -167,8 +161,6 @@ ui::WindowShowState PersistedShowStateToShowState(int state) {
       return ui::SHOW_STATE_MAXIMIZED;
     case PERSISTED_SHOW_STATE_FULLSCREEN:
       return ui::SHOW_STATE_FULLSCREEN;
-    case PERSISTED_SHOW_STATE_DOCKED_DEPRECATED:
-      return ui::SHOW_STATE_DOCKED;
     case PERSISTED_SHOW_STATE_DETACHED_DEPRECATED:
       return ui::SHOW_STATE_NORMAL;
   }