prompt: don't set default colors twice

The colors are set in __fish_config_interactive before the prompt is
painted for the first time.

Also initialize the $fish_color_status for the (pipe) status, bump the
version for that.
[ci skip]

share/functions/__fish_config_interactive.fish

@@ -44,9 +44,7 @@ function __fish_config_interactive -d "Initializations that should be performed
 
     #
     # If we are starting up for the first time, set various defaults.
-    #
+    if not set -q __fish_init_3_1_0
-    # bump this to 2_4_0 when rolling release if anything changes after 9/10/2016
-    if not set -q __fish_init_2_39_8
 
         # Regular syntax highlighting colors
         __init_uvar fish_color_normal normal
@@ -61,9 +59,9 @@ function __fish_config_interactive -d "Initializations that should be performed
         __init_uvar fish_color_quote 999900
         __init_uvar fish_color_autosuggestion 555 brblack
         __init_uvar fish_color_user brgreen
-
         __init_uvar fish_color_host normal
         __init_uvar fish_color_valid_path --underline
+        __init_uvar fish_color_status red
 
         __init_uvar fish_color_cwd green
         __init_uvar fish_color_cwd_root red
@@ -92,7 +90,8 @@ function __fish_config_interactive -d "Initializations that should be performed
         #
         __init_uvar fish_color_history_current --bold
 
-        set -U __fish_init_2_39_8
+        set -e __fish_init_2_39_8
+        set -U __fish_init_3_1_0
     end
 
     #

share/functions/fish_prompt.fish

@@ -5,13 +5,8 @@ function fish_prompt --description 'Write out the prompt'
     set -l last_pipestatus $pipestatus
     set -l normal (set_color normal)
 
-    # Initialize our variables.
-    set -q fish_color_user
-    or set -U fish_color_user -o green
     set -q fish_color_host
     or set -U fish_color_host -o cyan
-    set -q fish_color_status
-    or set -U fish_color_status red
 
     # Color the prompt differently when we're root
     set -l color_cwd $fish_color_cwd

share/tools/web_config/sample_prompts/classic_status.fish

@@ -5,9 +5,6 @@ function fish_prompt --description "Write out the prompt"
     # Save our status
     set -l last_pipestatus $pipestatus
 
-    set -q fish_color_status
-    or set -U fish_color_status red
-
     set -l color_cwd
     set -l suffix
     switch "$USER"

share/tools/web_config/sample_prompts/classic_vcs.fish

@@ -7,12 +7,8 @@ function fish_prompt --description 'Write out the prompt'
     set -l normal (set_color normal)
 
     # Initialize our variables.
-    set -q fish_color_user
-    or set -U fish_color_user -o green
     set -q fish_color_host
     or set -U fish_color_host -o cyan
-    set -q fish_color_status
-    or set -U fish_color_status red
 
     # Color the prompt differently when we're root
     set -l color_cwd $fish_color_cwd

share/tools/web_config/sample_prompts/informative.fish

@@ -5,9 +5,6 @@ function fish_prompt --description 'Informative prompt'
     #Save the return status of the previous command
     set -l last_pipestatus $pipestatus
 
-    set -q fish_color_status
-    or set -U fish_color_status red
-
     switch "$USER"
         case root toor
             printf '%s@%s %s%s%s# ' $USER (prompt_hostname) (set -q fish_color_cwd_root

share/tools/web_config/sample_prompts/informative_vcs.fish

@@ -56,9 +56,6 @@ function fish_prompt --description 'Write out the prompt'
         set -g __fish_git_prompt_color_cleanstate green --bold
     end
 
-    set -q fish_color_status
-    or set -U fish_color_status red
-
     set -l color_cwd
     set -l prefix
     set -l suffix