Revert of Preserve autosizing multiplier on style recalc.

Source/core/page/Page.cpp

Index: Source/core/page/Page.cpp
diff --git a/Source/core/page/Page.cpp b/Source/core/page/Page.cpp
index 2530af92a517b260752070675d004691affc9c68..a5986abd7e881ebf5f3bb49056b6105c65251e86 100644
--- a/Source/core/page/Page.cpp
+++ b/Source/core/page/Page.cpp
@@ -51,7 +51,6 @@
 #include "core/page/StorageClient.h"
 #include "core/page/ValidationMessageClient.h"
 #include "core/page/scrolling/ScrollingCoordinator.h"
-#include "core/rendering/FastTextAutosizer.h"
 #include "core/rendering/RenderView.h"
 #include "core/rendering/TextAutosizer.h"
 #include "core/storage/StorageNamespace.h"
@@ -489,19 +488,20 @@ void Page::settingsChanged(SettingsDelegate::ChangeType changeType)
         }
         break;
     case SettingsDelegate::TextAutosizingChange:
-        if (!mainFrame())
-            break;
-        if (FastTextAutosizer* textAutosizer = mainFrame()->document()->fastTextAutosizer()) {
-            textAutosizer->updatePageInfoInAllFrames();
+        // FTA needs both setNeedsRecalcStyle and setNeedsLayout after a setting change.
+        if (RuntimeEnabledFeatures::fastTextAutosizingEnabled()) {
+            setNeedsRecalcStyleInAllFrames();
         } else {
+            // FIXME: I wonder if this needs to traverse frames like in WebViewImpl::resize, or whether there is only one document per Settings instance?
             for (LocalFrame* frame = mainFrame(); frame; frame = frame->tree().traverseNext()) {
-                if (TextAutosizer* textAutosizer = frame->document()->textAutosizer())
+                TextAutosizer* textAutosizer = frame->document()->textAutosizer();
+                if (textAutosizer)
                     textAutosizer->recalculateMultipliers();
             }
-            // TextAutosizing updates RenderStyle during layout phase (via TextAutosizer::processSubtree).
-            // We should invoke setNeedsLayout here.
-            setNeedsLayoutInAllFrames();
         }
+        // TextAutosizing updates RenderStyle during layout phase (via TextAutosizer::processSubtree).
+        // We should invoke setNeedsLayout here.
+        setNeedsLayoutInAllFrames();
         break;
     case SettingsDelegate::ScriptEnableChange:
         m_inspectorController->scriptsEnabled(settings().scriptEnabled());