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

Source/core/html/forms/StepRange.cpp

Index: Source/core/html/forms/StepRange.cpp
diff --git a/Source/core/html/forms/StepRange.cpp b/Source/core/html/forms/StepRange.cpp
index 62a3afac9b47be031dc26a11f069d001d9ebbb07..cba592c5799eccfe73eda8440207bf80861b04e3 100644
--- a/Source/core/html/forms/StepRange.cpp
+++ b/Source/core/html/forms/StepRange.cpp
@@ -27,8 +27,6 @@
 #include "wtf/text/WTFString.h"
 #include <float.h>
 
-using namespace std;
-
 namespace WebCore {
 
 using namespace HTMLNames;
@@ -84,7 +82,7 @@ Decimal StepRange::alignValueForStep(const Decimal& currentValue, const Decimal&
 
 Decimal StepRange::clampValue(const Decimal& value) const
 {
-    const Decimal inRangeValue = max(m_minimum, min(value, m_maximum));
+    const Decimal inRangeValue = std::max(m_minimum, std::min(value, m_maximum));
     if (!m_hasStep)
         return inRangeValue;
     // Rounds inRangeValue to stepBase + N * step.
@@ -121,13 +119,13 @@ Decimal StepRange::parseStep(AnyStepHandling anyStepHandling, const StepDescript
         break;
     case ParsedStepValueShouldBeInteger:
         // For date, month, and week, the parsed value should be an integer for some types.
-        step = max(step.round(), Decimal(1));
+        step = std::max(step.round(), Decimal(1));
         step *= stepDescription.stepScaleFactor;
         break;
     case ScaledStepValueShouldBeInteger:
         // For datetime, datetime-local, time, the result should be an integer.
         step *= stepDescription.stepScaleFactor;
-        step = max(step.round(), Decimal(1));
+        step = std::max(step.round(), Decimal(1));
         break;
     default:
         ASSERT_NOT_REACHED();