From f8c7cc5706ea00af2424bc4bde628b95ca14e8e4 Mon Sep 17 00:00:00 2001
From: Dmitry Batrak <Dmitry.Batrak@jetbrains.com>
Date: Tue, 26 May 2015 16:26:35 +0300
Subject: [PATCH] IDEA-139761 Incorrect rendering of scrollbar track (following
 IDEA-CR-2863)

---
 .../openapi/editor/impl/EditorImpl.java        | 18 +++++++++++-------
 1 file changed, 11 insertions(+), 7 deletions(-)

diff --git a/platform/platform-impl/src/com/intellij/openapi/editor/impl/EditorImpl.java b/platform/platform-impl/src/com/intellij/openapi/editor/impl/EditorImpl.java
index 0ceed06ffbbe..3070ec362c2a 100644
--- a/platform/platform-impl/src/com/intellij/openapi/editor/impl/EditorImpl.java
+++ b/platform/platform-impl/src/com/intellij/openapi/editor/impl/EditorImpl.java
@@ -2415,10 +2415,11 @@ public final class EditorImpl extends UserDataHolderBase implements EditorEx, Hi
     Point position = new Point(0, visibleLine * lineHeight);
     CharSequence prefixText = myPrefixText == null ? null : new CharArrayCharSequence(myPrefixText);
     if (clipStartVisualPos.line == 0 && prefixText != null) {
-      position.x = drawBackground(g, prevBackColor = myPrefixAttributes.getBackgroundColor(), prefixText, 0, prefixText.length(), position,
+      Color backColor = myPrefixAttributes.getBackgroundColor();
+      position.x = drawBackground(g, backColor, prefixText, 0, prefixText.length(), position,
                                   myPrefixAttributes.getFontType(),
                                   defaultBackground, clip);
-      
+      prevBackColor = backColor;
     }
 
     if (clipStartPosition.line >= myDocument.getLineCount() || clipStartPosition.line < 0) {
@@ -2469,7 +2470,8 @@ public final class EditorImpl extends UserDataHolderBase implements EditorEx, Hi
       }
 
       if (color != null) {
-        drawBackground(g, prevBackColor = color, softWrap.getIndentInPixels(), position, defaultBackground, clip);
+        drawBackground(g, color, softWrap.getIndentInPixels(), position, defaultBackground, clip);
+        prevBackColor = color;
       }
       position.x = softWrap.getIndentInPixels();
     }
@@ -2525,7 +2527,8 @@ public final class EditorImpl extends UserDataHolderBase implements EditorEx, Hi
             );
           }
           CharSequence chars = collapsedFolderAt.getPlaceholderText();
-          position.x = drawBackground(g, prevBackColor = backColor, chars, 0, chars.length(), position, fontType, defaultBackground, clip);
+          position.x = drawBackground(g, backColor, chars, 0, chars.length(), position, fontType, defaultBackground, clip);
+          prevBackColor = backColor;
         }
 
         lIterator.advance();
@@ -2541,7 +2544,8 @@ public final class EditorImpl extends UserDataHolderBase implements EditorEx, Hi
             );
           }
           CharSequence chars = collapsedFolderAt.getPlaceholderText();
-          position.x = drawBackground(g, prevBackColor = backColor, chars, 0, chars.length(), position, fontType, defaultBackground, clip);
+          position.x = drawBackground(g, backColor, chars, 0, chars.length(), position, fontType, defaultBackground, clip);
+          prevBackColor = backColor;
         }
         else if (hEnd > lEnd - lIterator.getSeparatorLength()) {
           position.x = drawSoftWrapAwareBackground(
@@ -2623,8 +2627,8 @@ public final class EditorImpl extends UserDataHolderBase implements EditorEx, Hi
   }
 
   private int drawSoftWrapAwareBackground(@NotNull Graphics g,
-                                          Color backColor,
-                                          Color prevBackColor,
+                                          @Nullable Color backColor,
+                                          @Nullable Color prevBackColor,
                                           @NotNull CharSequence text,
                                           int start,
                                           int end,