[gimp] app: adding comments for translators to shortened labels.

[Jehan Pagès <jehanp src gnome org>]

commit 6c9adcedc43a762d695399d3741d2f7d8e6bc23d
Author: Jehan <jehan girinstud io>
Date:   Mon Jan 8 16:07:10 2018 +0100

    app: adding comments for translators to shortened labels.
    
    These labels were shortened but it's difficult for translators to know
    what they are, especially when same shortened labels are common to
    different concepts.
    See commit 7ac7b9519f8417aae7f7fa34c8029f2beba4d707.

 app/widgets/gimpcolorframe.c |   32 ++++++++++++++++++++++++++++++++
 1 files changed, 32 insertions(+), 0 deletions(-)
---
diff --git a/app/widgets/gimpcolorframe.c b/app/widgets/gimpcolorframe.c
index e165642..f3dad4f 100644
--- a/app/widgets/gimpcolorframe.c
+++ b/app/widgets/gimpcolorframe.c
@@ -189,6 +189,7 @@ gimp_color_frame_init (GimpColorFrame *frame)
   frame->coords_box_x = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 6);
   gtk_box_pack_start (GTK_BOX (vbox), frame->coords_box_x, FALSE, FALSE, 0);
 
+  /* TRANSLATORS: X for the X coordinate. */
   label = gtk_label_new (_("X:"));
   gtk_box_pack_start (GTK_BOX (frame->coords_box_x), label, FALSE, FALSE, 0);
   gtk_widget_show (label);
@@ -202,6 +203,7 @@ gimp_color_frame_init (GimpColorFrame *frame)
   frame->coords_box_y = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 6);
   gtk_box_pack_start (GTK_BOX (vbox), frame->coords_box_y, FALSE, FALSE, 0);
 
+  /* TRANSLATORS: Y for the Y coordinate. */
   label = gtk_label_new (_("Y:"));
   gtk_box_pack_start (GTK_BOX (frame->coords_box_y), label, FALSE, FALSE, 0);
   gtk_widget_show (label);
@@ -631,7 +633,9 @@ gimp_color_frame_update (GimpColorFrame *frame)
     }
   else
     {
+      /* TRANSLATORS: n/a for Not Available. */
       gtk_label_set_text (GTK_LABEL (frame->coords_label_x), _("n/a"));
+      /* TRANSLATORS: n/a for Not Available. */
       gtk_label_set_text (GTK_LABEL (frame->coords_label_y), _("n/a"));
     }
 
@@ -704,18 +708,24 @@ gimp_color_frame_update (GimpColorFrame *frame)
 
         if (base_type == GIMP_GRAY)
           {
+            /* TRANSLATORS: V for Value (grayscale) */
             names[0] = _("V:");
 
             if (has_alpha)
+              /* TRANSLATORS: A for Alpha (color transparency) */
               names[1] = _("A:");
           }
         else
           {
+            /* TRANSLATORS: R for Red (RGB) */
             names[0] = _("R:");
+            /* TRANSLATORS: G for Green (RGB) */
             names[1] = _("G:");
+            /* TRANSLATORS: B for Blue (RGB) */
             names[2] = _("B:");
 
             if (has_alpha)
+              /* TRANSLATORS: A for Alpha (color transparency) */
               names[3] = _("A:");
 
             if (babl_format_is_palette (frame->sample_format))
@@ -742,13 +752,18 @@ gimp_color_frame_update (GimpColorFrame *frame)
 
     case GIMP_COLOR_FRAME_MODE_RGB_PERCENT:
     case GIMP_COLOR_FRAME_MODE_RGB_U8:
+      /* TRANSLATORS: R for Red (RGB) */
       names[0] = _("R:");
+      /* TRANSLATORS: G for Green (RGB) */
       names[1] = _("G:");
+      /* TRANSLATORS: B for Blue (RGB) */
       names[2] = _("B:");
 
       if (has_alpha)
+        /* TRANSLATORS: A for Alpha (color transparency) */
         names[3] = _("A:");
 
+      /* TRANSLATORS: Hex for Hexadecimal (representation of a color) */
       names[4] = _("Hex:");
 
       if (frame->sample_valid)
@@ -779,11 +794,15 @@ gimp_color_frame_update (GimpColorFrame *frame)
       break;
 
     case GIMP_COLOR_FRAME_MODE_HSV:
+      /* TRANSLATORS: H for Hue (HSV color space) */
       names[0] = _("H:");
+      /* TRANSLATORS: S for Saturation (HSV color space) */
       names[1] = _("S:");
+      /* TRANSLATORS: V for Value (HSV color space) */
       names[2] = _("V:");
 
       if (has_alpha)
+        /* TRANSLATORS: A for Alpha (color transparency) */
         names[3] = _("A:");
 
       if (frame->sample_valid)
@@ -803,11 +822,15 @@ gimp_color_frame_update (GimpColorFrame *frame)
       break;
 
     case GIMP_COLOR_FRAME_MODE_LCH:
+      /* TRANSLATORS: L for Lightness (LCH color space) */
       names[0] = _("L:");
+      /* TRANSLATORS: C for Chroma (LCH color space) */
       names[1] = _("C:");
+      /* TRANSLATORS: H for Hue (LCH color space) */
       names[2] = _("H:");
 
       if (has_alpha)
+        /* TRANSLATORS: A for Alpha (color transparency) */
         names[3] = _("A:");
 
       if (frame->sample_valid)
@@ -831,11 +854,15 @@ gimp_color_frame_update (GimpColorFrame *frame)
       break;
 
     case GIMP_COLOR_FRAME_MODE_LAB:
+      /* TRANSLATORS: L for Lightness (Lab color space) */
       names[0] = _("L:");
+      /* TRANSLATORS: a* color channel in Lab color space */
       names[1] = _("A:");
+      /* TRANSLATORS: b* color channel in Lab color space */
       names[2] = _("B:");
 
       if (has_alpha)
+        /* TRANSLATORS: A for Alpha (color transparency) */
         names[3] = _("A:");
 
       if (frame->sample_valid)
@@ -859,12 +886,17 @@ gimp_color_frame_update (GimpColorFrame *frame)
       break;
 
     case GIMP_COLOR_FRAME_MODE_CMYK:
+      /* TRANSLATORS: C for Cyan (CMYK) */
       names[0] = _("C:");
+      /* TRANSLATORS: M for Magenta (CMYK) */
       names[1] = _("M:");
+      /* TRANSLATORS: Y for Yellow (CMYK) */
       names[2] = _("Y:");
+      /* TRANSLATORS: K for Key/black (CMYK) */
       names[3] = _("K:");
 
       if (has_alpha)
+        /* TRANSLATORS: A for Alpha (color transparency) */
         names[4] = _("A:");
 
       if (frame->sample_valid)