Distribute BoolToOnOff Away from ExampleBase

BoolToOnOff isn't generally useful to all examples.

BUG=897377
TBR=sky@chromium.org

Change-Id: Ic3738b32db1cd4f06651e5609f664b8aaa52943d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1540365Reviewed-by: Robert Liao <robliao@chromium.org>
Commit-Queue: Robert Liao <robliao@chromium.org>
Cr-Commit-Position: refs/heads/master@{#644585}

ui/views/examples/example_base.h

@@ -33,11 +33,6 @@ class VIEWS_EXAMPLES_EXPORT ExampleBase {
   // Prints a message in the status area, at the bottom of the window.
   void PrintStatus(const char* format, ...);
 
-  // Converts an boolean value to "on" or "off".
-  const char* BoolToOnOff(bool value) {
-    return value ? "on" : "off";
-  }
-
  private:
   // Name of the example - used as title in the combobox list.
   std::string example_title_;

ui/views/examples/message_box_example.cc

@@ -54,7 +54,7 @@ void MessageBoxExample::CreateExampleView(View* container) {
 void MessageBoxExample::ButtonPressed(Button* sender, const ui::Event& event) {
   if (sender == status_) {
     message_box_view_->SetCheckBoxLabel(
-        ASCIIToUTF16(BoolToOnOff(message_box_view_->IsCheckBoxSelected())));
+        ASCIIToUTF16(message_box_view_->IsCheckBoxSelected() ? "on" : "off"));
     PrintStatus(message_box_view_->IsCheckBoxSelected() ?
        "Check Box Selected" : "Check Box Not Selected");
   } else if (sender == toggle_) {

ui/views/examples/radio_button_example.cc

@@ -17,6 +17,14 @@
 namespace views {
 namespace examples {
 
+namespace {
+
+const char* BoolToOnOff(bool value) {
+  return value ? "on" : "off";
+}
+
+}  // namespace
+
 RadioButtonExample::RadioButtonExample() : ExampleBase("Radio Button") {}
 
 RadioButtonExample::~RadioButtonExample() = default;