Tracking issue: Text input and selection

This bug tracks remaining issues in text input and selection in both text inputs and in the document.

• #7492
  • DOM selection should be represented in the composed tree:
    • #47119
    • #47118
    • #47117
    • #47120
    • #47121
• #47896
  • Stringifier / clipboard copy
  • Ensure style is up to day when calling used_user_select()
• Mouse
  • #4409
  • #48107
  • #48101
  • Hit testing should find closest DOM position for selection regardless of whether it is a child of the hit node and take into account layout mode.
  • Selecting beyond the edge of an input or the window should scroll
  • Document selection should support expanding the selection to word / paragraph with double / triple click
  • Caret/text selection positioning does not account for RTL text properly
• Keyboard
  • #47897
  • Copying a selection via the keyboard
  • Changing the selection focus point via the keyboard
    • Glyph
    • Word
    • Line
• Rendering
  • #47392
  • #36924
  • #11302
  • #48149

Completed

• Text selection is deleted on focus change #39025
• Text is selected on focus #39026
• #39028
• The caret will be shown at end of previous text segment in Text Area due to improper range calculation
• Mouse selection does not work within text area or text input #10083
• The caret is not blinking #33237
• The caret/text selection does not account for multiple glyph runs within a TextFragment properly
• This also leads to potential crash when dealing with specifically text input due to a hack to prevent text input being trimmed #36449
• Caret will not be rendered when there's no text in text area