Accessibility improvements: Source Text.

Screen Readers such as JAWS always try to speak a name for a control
when it gains focus. For a text control a screen reader will often
obtain the name from the static text object that immediately precedes
the text control in the window hierarchy. It will use the text of the
static text object that immediately precedes the text control in the
window hierarchy even if that static text object is currently hidden.
This allows developers to make accessibly changes to their application
without affecting the visual appearance of their application.

For the m_textOrig object, the label the immediately precedes the
control is the m_labelSingular object. This causes screen readers such
as JAWS to speak Singular when the m_textOrig object gains focus, even
if the Plural Form UI is disabled. This is confusing for screen readers.

The solution is quite simple. When the Plural Form UI is disabled, the
label text of the m_labelSingular object is set to "Source text:." When
the Plural Form UI is enabled, the label text of the m_labelSingular
object is set to "Singular:."

This change was requested by Freedom Scientific.

src/edframe.cpp

@@ -3322,6 +3322,30 @@ void PoeditFrame::ShowPluralFormUI(bool show)
     origSizer->Show(m_labelSingular, show);
     origSizer->Show(m_labelPlural, show);
     origSizer->Show(m_textOrigPlural, show);
+    /* Screen Readers such as JAWS always try to speak a name for a control when it gains focus. For
+    a text control a screen reader will often obtain the name from the static text object that
+    immediately precedes the text control in the window hierarchy. It will use the text of the
+    static text object that immediately precedes the text control in the window hierarchy even if
+    that static text object is currently hidden. This allows developers to make accessibly changes
+    to their application without affecting the visual appearance of their application.
+
+    For the m_textOrig object, the label the immediately precedes the control is the m_labelSingular
+    object. This causes screen readers such as JAWS to speak Singular when the m_textOrig object
+    gains focus, even if the Plural Form UI is disabled. This is confusing for screen readers.
+
+    The solution is quite simple. When the Plural Form UI is disabled, the label text of the
+    m_labelSingular object is set to "Source text:." When the Plural Form UI is enabled, the label
+    text of the m_labelSingular object is set to "Singular:."
+
+    This change was requested by Freedom Scientific. */
+    if (!show)
+    {
+        m_labelSingular->SetLabelText(_("Source text:"));
+    }
+    else
+    {
+        m_labelSingular->SetLabelText(_("Singular:"));
+    }
     origSizer->Layout();
 
     if (m_textTrans && m_pluralNotebook)