Revert of Removing "using" declarations that import names in the C++ Standard library.

Source/core/dom/ViewportDescription.cpp

Index: Source/core/dom/ViewportDescription.cpp
diff --git a/Source/core/dom/ViewportDescription.cpp b/Source/core/dom/ViewportDescription.cpp
index f6c88184eca18d469c3a538636c33c68595c5ef6..88e31cfe6dcbeadb706dfe0e93d9d811b6815ba4 100644
--- a/Source/core/dom/ViewportDescription.cpp
+++ b/Source/core/dom/ViewportDescription.cpp
@@ -35,6 +35,8 @@
 #include "core/frame/Settings.h"
 #include "platform/weborigin/KURL.h"
 #include "public/platform/Platform.h"
+
+using namespace std;
 
 namespace WebCore {
 
@@ -110,13 +112,13 @@
 
     // 1. Resolve min-zoom and max-zoom values.
     if (resultMinZoom != ViewportDescription::ValueAuto && resultMaxZoom != ViewportDescription::ValueAuto)
-        resultMaxZoom = std::max(resultMinZoom, resultMaxZoom);
+        resultMaxZoom = max(resultMinZoom, resultMaxZoom);
 
     // 2. Constrain zoom value to the [min-zoom, max-zoom] range.
     if (resultZoom != ViewportDescription::ValueAuto)
-        resultZoom = compareIgnoringAuto(resultMinZoom, compareIgnoringAuto(resultMaxZoom, resultZoom, std::min), std::max);
-
-    float extendZoom = compareIgnoringAuto(resultZoom, resultMaxZoom, std::min);
+        resultZoom = compareIgnoringAuto(resultMinZoom, compareIgnoringAuto(resultMaxZoom, resultZoom, min), max);
+
+    float extendZoom = compareIgnoringAuto(resultZoom, resultMaxZoom, min);
 
     // 3. Resolve non-"auto" lengths to pixel lengths.
     if (extendZoom == ViewportDescription::ValueAuto) {
@@ -142,19 +144,19 @@
             resultMaxHeight = extendHeight;
 
         if (resultMinWidth == ViewportDescription::ValueExtendToZoom)
-            resultMinWidth = compareIgnoringAuto(extendWidth, resultMaxWidth, std::max);
+            resultMinWidth = compareIgnoringAuto(extendWidth, resultMaxWidth, max);
 
         if (resultMinHeight == ViewportDescription::ValueExtendToZoom)
-            resultMinHeight = compareIgnoringAuto(extendHeight, resultMaxHeight, std::max);
+            resultMinHeight = compareIgnoringAuto(extendHeight, resultMaxHeight, max);
     }
 
     // 4. Resolve initial width from min/max descriptors.
     if (resultMinWidth != ViewportDescription::ValueAuto || resultMaxWidth != ViewportDescription::ValueAuto)
-        resultWidth = compareIgnoringAuto(resultMinWidth, compareIgnoringAuto(resultMaxWidth, initialViewportSize.width(), std::min), std::max);
+        resultWidth = compareIgnoringAuto(resultMinWidth, compareIgnoringAuto(resultMaxWidth, initialViewportSize.width(), min), max);
 
     // 5. Resolve initial height from min/max descriptors.
     if (resultMinHeight != ViewportDescription::ValueAuto || resultMaxHeight != ViewportDescription::ValueAuto)
-        resultHeight = compareIgnoringAuto(resultMinHeight, compareIgnoringAuto(resultMaxHeight, initialViewportSize.height(), std::min), std::max);
+        resultHeight = compareIgnoringAuto(resultMinHeight, compareIgnoringAuto(resultMaxHeight, initialViewportSize.height(), min), max);
 
     // 6-7. Resolve width value.
     if (resultWidth == ViewportDescription::ValueAuto) {
@@ -178,7 +180,7 @@
             resultZoom = initialViewportSize.width() / resultWidth;
         if (resultHeight != ViewportDescription::ValueAuto && resultHeight > 0) {
             // if 'auto', the initial-scale will be negative here and thus ignored.
-            resultZoom = std::max<float>(resultZoom, initialViewportSize.height() / resultHeight);
+            resultZoom = max<float>(resultZoom, initialViewportSize.height() / resultHeight);
         }
     }