[Smart Lock] Add a private API to show an error bubble anchored to the Smart Lock app window.

ui/views/controls/styled_label.h

 // Copyright 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef UI_VIEWS_CONTROLS_STYLED_LABEL_H_
 #define UI_VIEWS_CONTROLS_STYLED_LABEL_H_
 
 #include <list>
 #include <map>
 
@@ skipping 72 matching lines @@
   // readable over it.
   void SetDisplayedOnBackgroundColor(SkColor color);
   SkColor displayed_on_background_color() const {
     return displayed_on_background_color_;
   }
 
   void set_auto_color_readability_enabled(bool auto_color_readability) {
     auto_color_readability_enabled_ = auto_color_readability;
   }
 
+  // Resizes the label so its width is set to the width of the longest line and
+  // its height deduced accordingly.
+  // This is only intended for multi-line labels and is useful when the label's
+  // text contains several lines separated with \n.
+  // |max_width| is the maximum width that will be used (longer lines will be
+  // wrapped). If 0, no maximum width is enforced.
+  void SizeToFit(int max_width);

[sky, 2015/01/20 16:24:36]

Isn't this the same as:

SetSize(gfx::Size(max_width, GetHeightForWidth(max_width)) ?

[Ilya Sherman, 2015/01/22 02:26:27]

Not quite.  SizeToFit will never size to a width greater than max_width, but it
will typically size to a smaller width -- whatever width is needed to fit the
text.  The result is that there isn't a bunch of awkward whitespace on the right
side of the bubble, where text could theoretically be drawn, but doesn't fit due
to word wrapping.

Note that I chose this name and max_width conventions to match the Label
implementation.

+
   // View implementation:
   gfx::Insets GetInsets() const override;
+  gfx::Size GetPreferredSize() const override;
   int GetHeightForWidth(int w) const override;
   void Layout() override;
   void PreferredSizeChanged() override;
 
   // LinkListener implementation:
   void LinkClicked(Link* source, int event_flags) override;
 
  private:
   struct StyleRange {
     StyleRange(const gfx::Range& range,
                const RangeStyleInfo& style_info)
         : range(range),
           style_info(style_info) {
     }
     ~StyleRange() {}
 
     bool operator<(const StyleRange& other) const;
 
     gfx::Range range;
     RangeStyleInfo style_info;
   };
   typedef std::list<StyleRange> StyleRanges;
 
-  // Calculates how to layout child views, creates them and sets their size
-  // and position. |width| is the horizontal space, in pixels, that the view
-  // has to work with. If |dry_run| is true, the view hierarchy is not touched.
-  // The return value is the necessary size.
+  // Calculates how to layout child views, creates them and sets their size and
+  // position. |width| is the horizontal space, in pixels, that the view has to
+  // work with. If |dry_run| is true, the view hierarchy is not touched. Caches
+  // the results in |calculated_size_|, |width_at_last_layout_|, and
+  // |width_at_last_size_calculation_|. Returns the needed size.
   gfx::Size CalculateAndDoLayout(int width, bool dry_run);
 
   // The text to display.
   base::string16 text_;
 
   // Fonts used to display text. Can be augmented by RangeStyleInfo.
   gfx::FontList font_list_;
 
   // Line height.
   int specified_line_height_;
 
   // The default style to use for any part of the text that isn't within
   // a range in |style_ranges_|.
   RangeStyleInfo default_style_info_;
 
   // The listener that will be informed of link clicks.
   StyledLabelListener* listener_;
 
   // The ranges that should be linkified, sorted by start position.
   StyleRanges style_ranges_;
 
   // A mapping from a view to the range it corresponds to in |text_|. Only views
   // that correspond to ranges with is_link style set will be added to the map.
   std::map<View*, gfx::Range> link_targets_;
 
   // This variable saves the result of the last GetHeightForWidth call in order
   // to avoid repeated calculation.
   mutable gfx::Size calculated_size_;
+  mutable int width_at_last_size_calculation_;
   int width_at_last_layout_;
 
   // Background color on which the label is drawn, for auto color readability.
   SkColor displayed_on_background_color_;
   bool displayed_on_background_color_set_;
 
   // Controls whether the text is automatically re-colored to be readable on the
   // background.
   bool auto_color_readability_enabled_;
 
   DISALLOW_COPY_AND_ASSIGN(StyledLabel);
 };
 
 }  // namespace views
 
 #endif  // UI_VIEWS_CONTROLS_STYLED_LABEL_H_