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

Source/web/WebViewImpl.cpp

Index: Source/web/WebViewImpl.cpp
diff --git a/Source/web/WebViewImpl.cpp b/Source/web/WebViewImpl.cpp
index 05b17ac4098620fed46e90d51c3f57714a7eb2f8..c60757b86f7d6b1a778b03c8b206ae65457884ed 100644
--- a/Source/web/WebViewImpl.cpp
+++ b/Source/web/WebViewImpl.cpp
@@ -161,6 +161,7 @@
 #include <cmath> // for std::pow
 
 using namespace WebCore;
+using namespace std;
 
 // The following constants control parameters for automated scaling of webpages
 // (such as due to a double tap gesture or find in page etc.). These are
@@ -1064,13 +1065,13 @@
     const int absoluteSourceX = source.x + scrollOffset.width();
     if (leftMargin > absoluteSourceX) {
         leftMargin = absoluteSourceX;
-        rightMargin = std::max(leftMargin, minimumMargin);
+        rightMargin = max(leftMargin, minimumMargin);
     }
 
     const int maximumRightMargin = maxSize.width - (source.width + absoluteSourceX);
     if (rightMargin > maximumRightMargin) {
         rightMargin = maximumRightMargin;
-        leftMargin = std::min(leftMargin, std::max(rightMargin, minimumMargin));
+        leftMargin = min(leftMargin, max(rightMargin, minimumMargin));
     }
 
     const int newWidth = source.width + leftMargin + rightMargin;
@@ -1115,9 +1116,9 @@
                 static_cast<int>(minimumMargin * rect.width / m_size.width));
         // Fit block to screen, respecting limits.
         scale = static_cast<float>(m_size.width) / rect.width;
-        scale = std::min(scale, legibleScale());
+        scale = min(scale, legibleScale());
         if (pageScaleFactor() < defaultScaleWhenAlreadyLegible)
-            scale = std::max(scale, defaultScaleWhenAlreadyLegible);
+            scale = max(scale, defaultScaleWhenAlreadyLegible);
         scale = clampPageScaleFactorToLimits(scale);
     }
 
@@ -1138,14 +1139,14 @@
     } else {
         // Ensure position we're zooming to (+ padding) isn't off the bottom of
         // the screen.
-        rect.y = std::max<float>(rect.y, hitPoint.y + padding - screenHeight);
+        rect.y = max<float>(rect.y, hitPoint.y + padding - screenHeight);
     } // Otherwise top align the block.
 
     // Do the same thing for horizontal alignment.
     if (rect.width < screenWidth)
         rect.x -= 0.5 * (screenWidth - rect.width);
     else
-        rect.x = std::max<float>(rect.x, hitPoint.x + padding - screenWidth);
+        rect.x = max<float>(rect.x, hitPoint.x + padding - screenWidth);
     scroll.x = rect.x;
     scroll.y = rect.y;
 
@@ -2605,11 +2606,11 @@
         // onscreen.
         int idealLeftPadding = viewWidth * leftBoxRatio;
         int maxLeftPaddingKeepingBoxOnscreen = viewWidth - textboxRectInDocumentCoordinates.width();
-        newScroll.setX(textboxRectInDocumentCoordinates.x() - std::min<int>(idealLeftPadding, maxLeftPaddingKeepingBoxOnscreen));
+        newScroll.setX(textboxRectInDocumentCoordinates.x() - min<int>(idealLeftPadding, maxLeftPaddingKeepingBoxOnscreen));
     } else {
         // Field is wider than screen. Try to left-align field, unless caret would
         // be offscreen, in which case right-align the caret.
-        newScroll.setX(std::max<int>(textboxRectInDocumentCoordinates.x(), caretInDocumentCoordinates.x() + caretInDocumentCoordinates.width() + caretPadding - viewWidth));
+        newScroll.setX(max<int>(textboxRectInDocumentCoordinates.x(), caretInDocumentCoordinates.x() + caretInDocumentCoordinates.width() + caretPadding - viewWidth));
     }
     if (textboxRectInDocumentCoordinates.height() <= viewHeight) {
         // Field is shorter than screen. Vertically center it.
@@ -2617,7 +2618,7 @@
     } else {
         // Field is taller than screen. Try to top align field, unless caret would
         // be offscreen, in which case bottom-align the caret.
-        newScroll.setY(std::max<int>(textboxRectInDocumentCoordinates.y(), caretInDocumentCoordinates.y() + caretInDocumentCoordinates.height() + caretPadding - viewHeight));
+        newScroll.setY(max<int>(textboxRectInDocumentCoordinates.y(), caretInDocumentCoordinates.y() + caretInDocumentCoordinates.height() + caretPadding - viewHeight));
     }
 
     needAnimation = false;
@@ -2694,7 +2695,7 @@
     if (zoomLevel == m_zoomLevel)
         return;
 
-    m_zoomLevel = std::max(std::min(zoomLevel, m_maximumZoomLevel), m_minimumZoomLevel);
+    m_zoomLevel = max(min(zoomLevel, m_maximumZoomLevel), m_minimumZoomLevel);
     m_client->zoomLevelChanged();
 }