Remove image decoder and encoder autoregistration

src/images/SkImageDecoder_libwebp.cpp

Index: src/images/SkImageDecoder_libwebp.cpp
diff --git a/src/images/SkImageDecoder_libwebp.cpp b/src/images/SkImageDecoder_libwebp.cpp
index f32587ddcc2427c1e3630cd5285f1049aaf71224..a74c907b5beea17b7e012718d2af67b6331b275f 100644
--- a/src/images/SkImageDecoder_libwebp.cpp
+++ b/src/images/SkImageDecoder_libwebp.cpp
@@ -14,8 +14,8 @@
  * limitations under the License.
  */
 
-#include "SkImageDecoder.h"
-#include "SkImageEncoder.h"
+#include "SkImageDecoder_libwebp.h"
+
 #include "SkColorPriv.h"
 #include "SkScaledBitmapSampler.h"
 #include "SkStream.h"
@@ -589,6 +589,21 @@ static int stream_writer(const uint8_t* data, size_t data_size,
   return stream->write(data, data_size) ? 1 : 0;
 }
 
+SkImageDecoder::Format SkDetectFormatWEBPImageDecoder(SkStreamRewindable* stream) {
+    int width, height, hasAlpha;
+    if (webp_parse_header(stream, &width, &height, &hasAlpha)) {
+        return SkImageDecoder::kWEBP_Format;
+    }
+    return SkImageDecoder::kUnknown_Format;
+}
+
+SkImageDecoder* SkCreateWEBPImageDecoder(SkStreamRewindable* stream) {
+    if (SkDetectFormatWEBPImageDecoder(stream) == SkImageDecoder::kWEBP_Format) {
+        return SkNEW(SkWEBPImageDecoder);
+    }
+    return NULL;
+}
+
 class SkWEBPImageEncoder : public SkImageEncoder {
 protected:
     virtual bool onEncode(SkWStream* stream, const SkBitmap& bm, int quality) SK_OVERRIDE;
@@ -653,34 +668,6 @@ bool SkWEBPImageEncoder::onEncode(SkWStream* stream, const SkBitmap& bm,
     return ok;
 }
 
-
-///////////////////////////////////////////////////////////////////////////////
-DEFINE_DECODER_CREATOR(WEBPImageDecoder);
-DEFINE_ENCODER_CREATOR(WEBPImageEncoder);
-///////////////////////////////////////////////////////////////////////////////
-
-static SkImageDecoder* sk_libwebp_dfactory(SkStreamRewindable* stream) {
-    int width, height, hasAlpha;
-    if (!webp_parse_header(stream, &width, &height, &hasAlpha)) {
-        return NULL;
-    }
-
-    // Magic matches, call decoder
-    return SkNEW(SkWEBPImageDecoder);
-}
-
-static SkImageDecoder::Format get_format_webp(SkStreamRewindable* stream) {
-    int width, height, hasAlpha;
-    if (webp_parse_header(stream, &width, &height, &hasAlpha)) {
-        return SkImageDecoder::kWEBP_Format;
-    }
-    return SkImageDecoder::kUnknown_Format;
-}
-
-static SkImageEncoder* sk_libwebp_efactory(SkImageEncoder::Type t) {
-      return (SkImageEncoder::kWEBP_Type == t) ? SkNEW(SkWEBPImageEncoder) : NULL;
+SkImageEncoder* SkCreateWEBPImageEncoder(SkImageEncoder::Type t) {
+    return (SkImageEncoder::kWEBP_Type == t) ? SkNEW(SkWEBPImageEncoder) : NULL;
 }
-
-static SkImageDecoder_DecodeReg gDReg(sk_libwebp_dfactory);
-static SkImageDecoder_FormatReg gFormatReg(get_format_webp);
-static SkImageEncoder_EncodeReg gEReg(sk_libwebp_efactory);