input[type=number] UI should reject invalid characters.

Source/platform/text/PlatformLocale.cpp

 /*
  * Copyright (C) 2011,2012 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 230 matching lines @@
     for (size_t i = 0; i < symbols.size(); ++i) {
         ASSERT(!symbols[i].isEmpty());
         m_decimalSymbols[i] = symbols[i];
     }
     m_positivePrefix = positivePrefix;
     m_positiveSuffix = positiveSuffix;
     m_negativePrefix = negativePrefix;
     m_negativeSuffix = negativeSuffix;
     ASSERT(!m_positivePrefix.isEmpty() || !m_positiveSuffix.isEmpty() || !m_negativePrefix.isEmpty() || !m_negativeSuffix.isEmpty());
     m_hasLocaleData = true;
+
+    StringBuilder builder;
+    for (size_t i = 0; i < DecimalSymbolsSize; ++i) {
+        // We don't accept group separatros.
+        if (i != GroupSeparatorIndex)
+            builder.append(m_decimalSymbols[i]);
+    }
+    builder.append(m_positivePrefix);
+    builder.append(m_positiveSuffix);
+    builder.append(m_negativePrefix);
+    builder.append(m_negativeSuffix);
+    m_acceptableNumberCharacters = builder.toString();
 }
 
 String Locale::convertToLocalizedNumber(const String& input)
 {
     initializeLocaleData();
     if (!m_hasLocaleData || input.isEmpty())
         return input;
 
     unsigned i = 0;
     bool isNegative = false;
@@ skipping 113 matching lines @@
         if (symbolIndex == DecimalSeparatorIndex)
             builder.append('.');
         else if (symbolIndex == GroupSeparatorIndex)
             return input;
         else
             builder.append(static_cast<UChar>('0' + symbolIndex));
     }
     return builder.toString();
 }
 
+String Locale::stripInvalidNumberCharacters(const String& input, const String& standardChars) const
+{
+    StringBuilder builder;
+    builder.reserveCapacity(input.length());
+    for (unsigned i = 0; i < input.length(); ++i) {
+        UChar ch = input[i];
+        if (standardChars.find(ch) != kNotFound)
+            builder.append(ch);
+        else if (m_acceptableNumberCharacters.find(ch) != kNotFound)
+            builder.append(ch);
+    }
+    return builder.toString();
+}
+
 #if ENABLE(INPUT_MULTIPLE_FIELDS_UI)
 String Locale::localizedDecimalSeparator()
 {
     initializeLocaleData();
     return m_decimalSymbols[DecimalSeparatorIndex];
 }
 #endif
 
 String Locale::formatDateTime(const DateComponents& date, FormatType formatType)
 {
@@ skipping 19 matching lines @@
         builder.build(formatType == FormatTypeShort ? dateTimeFormatWithoutSeconds() : dateTimeFormatWithSeconds());
         break;
     case DateComponents::Invalid:
         ASSERT_NOT_REACHED();
         break;
     }
     return builder.toString();
 }
 
 } // namespace blink