SkColorTable locking serves no purpose anymore.

src/images/SkImageDecoder_libjpeg.cpp

 /*
  * Copyright 2007 The Android Open Source Project
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 
 #include "SkImageDecoder.h"
 #include "SkImageEncoder.h"
@@ skipping 1337 matching lines @@
         if (NULL == bm.getPixels()) {
             return false;
         }
 
         jpeg_compress_struct    cinfo;
         skjpeg_error_mgr        sk_err;
         skjpeg_destination_mgr  sk_wstream(stream);
 
         // allocate these before set call setjmp
         SkAutoMalloc    oneRow;
-        SkAutoLockColors ctLocker;
 
         cinfo.err = jpeg_std_error(&sk_err);
         sk_err.error_exit = skjpeg_error_exit;
         if (setjmp(sk_err.fJmpBuf)) {
             return false;
         }
 
         // Keep after setjmp or mark volatile.
         const WriteScanline writer = ChooseWriter(bm);
         if (NULL == writer) {
@@ skipping 16 matching lines @@
         jpeg_set_quality(&cinfo, quality, TRUE /* limit to baseline-JPEG values */);
 #ifdef DCT_IFAST_SUPPORTED
         cinfo.dct_method = JDCT_IFAST;
 #endif
 
         jpeg_start_compress(&cinfo, TRUE);
 
         const int       width = bm.width();
         uint8_t*        oneRowP = (uint8_t*)oneRow.reset(width * 3);
 
-        const SkPMColor* colors = ctLocker.lockColors(bm);
+        const SkPMColor* colors = bm.getColorTable() ? bm.getColorTable()->readColors() : NULL;
         const void*      srcRow = bm.getPixels();
 
         while (cinfo.next_scanline < cinfo.image_height) {
             JSAMPROW row_pointer[1];    /* pointer to JSAMPLE row[s] */
 
             writer(oneRowP, srcRow, width, colors);
             row_pointer[0] = oneRowP;
             (void) jpeg_write_scanlines(&cinfo, row_pointer, 1);
             srcRow = (const void*)((const char*)srcRow + bm.rowBytes());
         }
@@ skipping 41 matching lines @@
     return SkImageDecoder::kUnknown_Format;
 }
 
 static SkImageEncoder* sk_libjpeg_efactory(SkImageEncoder::Type t) {
     return (SkImageEncoder::kJPEG_Type == t) ? SkNEW(SkJPEGImageEncoder) : NULL;
 }
 
 static SkImageDecoder_DecodeReg gDReg(sk_libjpeg_dfactory);
 static SkImageDecoder_FormatReg gFormatReg(get_format_jpeg);
 static SkImageEncoder_EncodeReg gEReg(sk_libjpeg_efactory);