No longer register app window placement preference keys on the fly.

chrome/test/data/profiles/app_window_placement/Default/Preferences

Index: chrome/test/data/profiles/app_window_placement/Default/Preferences
diff --git a/chrome/test/data/profiles/app_window_placement/Default/Preferences b/chrome/test/data/profiles/app_window_placement/Default/Preferences
new file mode 100644
index 0000000000000000000000000000000000000000..e60d8442d85206e4d63c22f432a2421ba650ba70
--- /dev/null
+++ b/chrome/test/data/profiles/app_window_placement/Default/Preferences
@@ -0,0 +1,27 @@
+{
+   "browser": {
+      "window_placement": {
+         "bottom": 1181,
+         "left": 622,
+         "maximized": false,
+         "right": 1689,
+         "top": 28,
+         "work_area_bottom": 1576,
+         "work_area_left": 0,
+         "work_area_right": 2560,
+         "work_area_top": 24
+      },
+      "window_placement_DevToolsApp": {
+         "always_on_top": false,
+         "bottom": 693,
+         "left": 81,
+         "maximized": false,
+         "right": 721,
+         "top": 53,
+         "work_area_bottom": 1576,
+         "work_area_left": 0,
+         "work_area_right": 2560,
+         "work_area_top": 24
+      }

[gab, 2014/09/08 21:29:26]

Also add another test app which is not DevTools (since that's specific/known
app).

+   }
+}