Reset multipliers when FTA is disabled.

Source/core/rendering/FastTextAutosizer.cpp

 /*
  * Copyright (C) 2013 Google Inc. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met:
  *
  *     * Redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer.
  *     * Redistributions in binary form must reproduce the above
@@ skipping 273 matching lines @@
 #ifndef NDEBUG
         m_blocksThatHaveBegunLayout.add(block);
 #endif
         if (Cluster* cluster = maybeCreateCluster(block))
             m_clusterStack.append(adoptPtr(cluster));
     }
 }
 
 void FastTextAutosizer::beginLayout(RenderBlock* block)
 {
-    ASSERT(enabled() && m_pageNeedsAutosizing && !m_updatePageInfoDeferred);
+    ASSERT(enabled() && shouldHandleLayout());
 #ifndef NDEBUG
     m_blocksThatHaveBegunLayout.add(block);
 #endif
 
     if (!m_firstBlock)  {
         m_firstBlock = block;
         prepareClusterStack(block->parent());
     } else if (block == currentCluster()->m_root) {
         // Ignore beginLayout on the same block twice.
         // This can happen with paginated overflow.
         return;
     }
 
     if (Cluster* cluster = maybeCreateCluster(block)) {
         m_clusterStack.append(adoptPtr(cluster));
         if (block->isTable())
             inflateTable(toRenderTable(block));
     }
 
     if (block->childrenInline() && block->firstChild())
         inflate(block);
 }
 
 void FastTextAutosizer::inflateListItem(RenderListItem* listItem, RenderListMarker* listItemMarker)
 {
-    if (!enabled() || !m_pageNeedsAutosizing)
+    if (!enabled() || !shouldHandleLayout())
         return;
     ASSERT(listItem && listItemMarker);
 #ifndef NDEBUG
     m_blocksThatHaveBegunLayout.add(listItem);
 #endif
     // Force the LI to be inside the DBCAT when computing the multiplier.
     // This guarantees that the DBCAT has entered layout, so we can ask for its width.
     // It also makes sense because the list marker is autosized like a text node.
     float multiplier = clusterMultiplier(currentCluster());
 
@@ skipping 42 matching lines @@
                         }
                     }
                 }
             }
         }
     }
 }
 
 void FastTextAutosizer::endLayout(RenderBlock* block)
 {
-    ASSERT(enabled() && m_pageNeedsAutosizing);
+    ASSERT(enabled() && shouldHandleLayout());
 
     if (block == m_firstBlock) {
         m_firstBlock = 0;
         m_clusterStack.clear();
         m_superclusters.clear();
 #ifndef NDEBUG
         m_blocksThatHaveBegunLayout.clear();
 #endif
     } else if (currentCluster()->m_root == block) {
         m_clusterStack.removeLast();
@@ skipping 16 matching lines @@
             // has entered layout.
             if (!multiplier)
                 multiplier = cluster->m_autosize ? clusterMultiplier(cluster) : 1.0f;
             applyMultiplier(descendant, multiplier);
             applyMultiplier(descendant->parent(), multiplier); // Parent handles line spacing.
         }
         descendant = descendant->nextInPreOrder(block);
     }
 }
 
-bool FastTextAutosizer::enabled()
+bool FastTextAutosizer::enabled() const
 {
     if (!m_document->settings() || !m_document->page() || m_document->printing())
         return false;
 
     return m_document->settings()->textAutosizingEnabled();
 }
 
+bool FastTextAutosizer::shouldHandleLayout() const
+{
+    return m_pageNeedsAutosizing && !m_updatePageInfoDeferred;
+}
+
 void FastTextAutosizer::updatePageInfoInAllFrames()
 {
-    if (!enabled())
-        return;
-
-    ASSERT(m_document->frame()->isMainFrame());
+    ASSERT(!enabled() || m_document->frame()->isMainFrame());
 
     for (LocalFrame* frame = m_document->frame(); frame; frame = frame->tree().traverseNext()) {
         if (FastTextAutosizer* textAutosizer = frame->document()->fastTextAutosizer())
             textAutosizer->updatePageInfo();
     }
 }
 
 void FastTextAutosizer::updatePageInfo()
 {
-    if (!enabled() || m_updatePageInfoDeferred)
+    if (!enabled()) {
+        if (m_previouslyAutosized)
+            resetMultipliers();
+        return;
+    }
+
+    if (m_updatePageInfoDeferred)
         return;
 
     int previousFrameWidth = m_frameWidth;
     int previousLayoutWidth = m_layoutWidth;
     float previousBaseMultiplier = m_baseMultiplier;
 
     RenderView* renderView = toRenderView(m_document->renderer());
     bool horizontalWritingMode = isHorizontalWritingMode(renderView->style()->writingMode());
 
     LocalFrame* mainFrame = m_document->page()->mainFrame();
@@ skipping 515 matching lines @@
     return *m_blocksForFingerprint.get(fingerprint);
 }
 
 FastTextAutosizer::LayoutScope::LayoutScope(RenderBlock* block)
     : m_textAutosizer(block->document().fastTextAutosizer())
     , m_block(block)
 {
     if (!m_textAutosizer)
         return;
 
-    if (m_textAutosizer->enabled() && m_textAutosizer->m_pageNeedsAutosizing)
+    if (m_textAutosizer->enabled() && m_textAutosizer->shouldHandleLayout())
         m_textAutosizer->beginLayout(m_block);
     else
         m_textAutosizer = 0;
 }
 
 FastTextAutosizer::LayoutScope::~LayoutScope()
 {
     if (m_textAutosizer)
         m_textAutosizer->endLayout(m_block);
 }
@@ skipping 10 matching lines @@
 FastTextAutosizer::DeferUpdatePageInfo::~DeferUpdatePageInfo()
 {
     if (FastTextAutosizer* textAutosizer = m_mainFrame->document()->fastTextAutosizer()) {
         ASSERT(textAutosizer->m_updatePageInfoDeferred);
         textAutosizer->m_updatePageInfoDeferred = false;
         textAutosizer->updatePageInfoInAllFrames();
     }
 }
 
 } // namespace WebCore