Add support for CSS unicod encoding to the text codec.

third_party/WebKit/Source/wtf/text/TextCodecICU.cpp

Index: third_party/WebKit/Source/wtf/text/TextCodecICU.cpp
diff --git a/third_party/WebKit/Source/wtf/text/TextCodecICU.cpp b/third_party/WebKit/Source/wtf/text/TextCodecICU.cpp
index f90d447cebabc06f48162bf5f8de83b677797a5f..d3762707d253179feb5f27f43f8fa2ddae345683 100644
--- a/third_party/WebKit/Source/wtf/text/TextCodecICU.cpp
+++ b/third_party/WebKit/Source/wtf/text/TextCodecICU.cpp
@@ -414,6 +414,22 @@ static UChar fallbackForGBK(UChar32 character)
 
 // Invalid character handler when writing escaped entities for unrepresentable
 // characters. See the declaration of TextCodec::encode for more.
+static void cssEscapedEntityCallback(const void* context, UConverterFromUnicodeArgs* fromUArgs, const UChar* codeUnits, int32_t length,

[Dmitry Titov, 2016/02/18 21:26:48]

These two new functions are not really trivial copy/paste from "urlEscaped*"
variants. It's better to pull the common code into a separate one and call twice
with a parameter.

+    UChar32 codePoint, UConverterCallbackReason reason, UErrorCode* err)
+{
+    if (reason == UCNV_UNASSIGNED) {
+        *err = U_ZERO_ERROR;
+
+        UnencodableReplacementArray entity;
+        int entityLen = TextCodec::getUnencodableReplacement(codePoint, CSSEncodedEntitiesForUnencodables, entity);
+        ucnv_cbFromUWriteBytes(fromUArgs, entity, entityLen, 0, err);
+    } else {
+        UCNV_FROM_U_CALLBACK_ESCAPE(context, fromUArgs, codeUnits, length, codePoint, reason, err);
+    }
+}
+
+// Invalid character handler when writing escaped entities for unrepresentable
+// characters. See the declaration of TextCodec::encode for more.
 static void urlEscapedEntityCallback(const void* context, UConverterFromUnicodeArgs* fromUArgs, const UChar* codeUnits, int32_t length,
     UChar32 codePoint, UConverterCallbackReason reason, UErrorCode* err)
 {
@@ -443,6 +459,23 @@ static void gbkCallbackEscape(const void* context, UConverterFromUnicodeArgs* fr
     UCNV_FROM_U_CALLBACK_ESCAPE(context, fromUArgs, codeUnits, length, codePoint, reason, err);
 }
 
+// Combines both gbkCssEscapedEntityCallback and GBK character substitution.
+static void gbkCssEscapedEntityCallack(const void* context, UConverterFromUnicodeArgs* fromUArgs, const UChar* codeUnits, int32_t length,
+    UChar32 codePoint, UConverterCallbackReason reason, UErrorCode* err)
+{
+    if (reason == UCNV_UNASSIGNED) {
+        if (UChar outChar = fallbackForGBK(codePoint)) {
+            const UChar* source = &outChar;
+            *err = U_ZERO_ERROR;
+            ucnv_cbFromUWriteUChars(fromUArgs, &source, source + 1, 0, err);
+            return;
+        }
+        cssEscapedEntityCallback(context, fromUArgs, codeUnits, length, codePoint, reason, err);
+        return;
+    }
+    UCNV_FROM_U_CALLBACK_ESCAPE(context, fromUArgs, codeUnits, length, codePoint, reason, err);
+}
+
 // Combines both gbkUrlEscapedEntityCallback and GBK character substitution.
 static void gbkUrlEscapedEntityCallack(const void* context, UConverterFromUnicodeArgs* fromUArgs, const UChar* codeUnits, int32_t length,
     UChar32 codePoint, UConverterCallbackReason reason, UErrorCode* err)
@@ -530,6 +563,13 @@ CString TextCodecICU::encodeInternal(const TextCodecInput& input, UnencodableHan
         ucnv_setFromUCallBack(m_converterICU, m_needsGBKFallbacks ? gbkUrlEscapedEntityCallack : urlEscapedEntityCallback, 0, 0, 0, &err);
 #endif
         break;
+    case CSSEncodedEntitiesForUnencodables:
+#if !defined(USING_SYSTEM_ICU)
+        ucnv_setFromUCallBack(m_converterICU, cssEscapedEntityCallback, 0, 0, 0, &err);
+#else
+        ucnv_setFromUCallBack(m_converterICU, m_needsGBKFallbacks ? gbkCssEscapedEntityCallack : cssEscapedEntityCallback, 0, 0, 0, &err);
+#endif
+        break;
     }
 
     ASSERT(U_SUCCESS(err));