Move iOS WebP decoding to a component

This CL moves WebP decoding out of the web layer to a component that
does not depend on web.
This will allow to use the WebP decoding without pulling a dependency on
the web layer.

BUG=430110
TBR=cbentzel

Review URL: https://codereview.chromium.org/814013003

Cr-Commit-Position: refs/heads/master@{#309181}

21 files changed, 99 insertions, 85 deletions

diff --git a/components/OWNERS b/components/OWNERS
index 4de6407..8d00b69 100644
--- a/components/OWNERS
+++ b/components/OWNERS
@@ -249,6 +249,9 @@ per-file variations.gypi=stevet@chromium.org
 per-file webdata.gypi=pkasting@chromium.org
 per-file webdata_services.gypi=pkasting@chromium.org
 
+per-file webp_transcode.gypi=droger@chromium.org
+per-file webp_transcode.gypi=sdefresne@chromium.org
+
 per-file web_resource.gypi=asvitkine@chromium.org
 per-file web_resource.gypi=stevet@chromium.org
 
diff --git a/components/components.gyp b/components/components.gyp
index 91b5fc6..e011a89 100644
--- a/components/components.gyp
+++ b/components/components.gyp
@@ -81,6 +81,11 @@
         'web_modal.gypi',
       ],
     }],
+    ['OS == "ios"', {
+      'includes': [
+        'webp_transcode.gypi',
+      ],
+    }],
     ['OS != "android"', {
       'includes': [
         'feedback.gypi',
diff --git a/components/components_tests.gyp b/components/components_tests.gyp
index d7e1fea..922964e 100644
--- a/components/components_tests.gyp
+++ b/components/components_tests.gyp
@@ -598,6 +598,9 @@
               ],
             }, { # 'OS == "ios"'
               'includes': ['../chrome/chrome_ios_bundle_resources.gypi'],
+              'sources': [
+                'webp_transcode/webp_decoder_unittest.mm',
+              ],
               'sources/': [
                 ['exclude', '\\.cc$'],
                 ['exclude', '\\.mm$'],
@@ -635,6 +638,7 @@
                 ['include', '^translate/'],
                 ['include', '^url_fixer/'],
                 ['include', '^variations/'],
+                ['include', '^webp_transcode/'],
               ],
               'dependencies': [
                 # Dependencies of sessions
@@ -646,6 +650,9 @@
                 # Dependencies of translate
                 'components.gyp:translate_ios_browser',
 
+                # Dependencies of webp_transcode
+                'components.gyp:webp_transcode',
+
                 '../ios/ios_tests.gyp:test_support_ios',
                 '../ios/web/ios_web.gyp:test_support_ios_web',
                 '../third_party/ocmock/ocmock.gyp:ocmock',
diff --git a/ios/web/test/data/test.jpg b/components/test/data/webp_transcode/test.jpg
index 182a14a..182a14a 100644
--- a/ios/web/test/data/test.jpg
+++ b/components/test/data/webp_transcode/test.jpg
diff --git a/ios/web/test/data/test.webp b/components/test/data/webp_transcode/test.webp
index 122741b..122741b 100644
--- a/ios/web/test/data/test.webp
+++ b/components/test/data/webp_transcode/test.webp
diff --git a/ios/web/test/data/test_alpha.png b/components/test/data/webp_transcode/test_alpha.png
index 2de1a48..2de1a48 100644
--- a/ios/web/test/data/test_alpha.png
+++ b/components/test/data/webp_transcode/test_alpha.png
diff --git a/ios/web/test/data/test_alpha.webp b/components/test/data/webp_transcode/test_alpha.webp
index ba39447..ba39447 100644
--- a/ios/web/test/data/test_alpha.webp
+++ b/components/test/data/webp_transcode/test_alpha.webp
diff --git a/ios/web/test/data/test_small.tiff b/components/test/data/webp_transcode/test_small.tiff
index 8f1986d..8f1986d 100644
--- a/ios/web/test/data/test_small.tiff
+++ b/components/test/data/webp_transcode/test_small.tiff
diff --git a/ios/web/test/data/test_small.webp b/components/test/data/webp_transcode/test_small.webp
index 5447184..5447184 100644
--- a/ios/web/test/data/test_small.webp
+++ b/components/test/data/webp_transcode/test_small.webp
diff --git a/components/webp_transcode.gypi b/components/webp_transcode.gypi
new file mode 100644
index 0000000..b99003c
--- /dev/null
+++ b/components/webp_transcode.gypi
@@ -0,0 +1,24 @@
+# Copyright 2013 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+{
+  'targets': [
+    {
+      'target_name': 'webp_transcode',
+      'type': 'static_library',
+      'dependencies': [
+        '../base/base.gyp:base',
+        '../net/net.gyp:net',
+        '../third_party/libwebp/libwebp.gyp:libwebp_dec',
+      ],
+      'include_dirs': [
+        '..',
+      ],
+      'sources': [
+        'webp_transcode/webp_decoder.h',
+        'webp_transcode/webp_decoder.mm',
+       ],
+    },
+  ],
+}
diff --git a/components/webp_transcode/DEPS b/components/webp_transcode/DEPS
new file mode 100644
index 0000000..0e26ac6
--- /dev/null
+++ b/components/webp_transcode/DEPS
@@ -0,0 +1,10 @@
+include_rules = [
+  "+net",
+  # Only WebP decoding is allowed (no encoding).
+  "+third_party/libwebp/webp/decode.h",
+
+  # webp_transcode should not depend on //ios for library size reasons.
+  "-ios",
+  # webp_transcode is only used by iOS.
+  "-content",
+]
diff --git a/components/webp_transcode/OWNERS b/components/webp_transcode/OWNERS
new file mode 100644
index 0000000..fa3d0c2
--- /dev/null
+++ b/components/webp_transcode/OWNERS
@@ -0,0 +1,2 @@
+droger@chromium.org
+sdefresne@chromium.org
diff --git a/components/webp_transcode/README b/components/webp_transcode/README
new file mode 100644
index 0000000..4484825
--- /dev/null
+++ b/components/webp_transcode/README
@@ -0,0 +1,2 @@
+webp_transcode is used to convert WebP images to other formats supported by the
+iOS web views.
diff --git a/ios/web/public/webp_decoder.h b/components/webp_transcode/webp_decoder.h
index 8700718..64126c2 100644
--- a/ios/web/public/webp_decoder.h
+++ b/components/webp_transcode/webp_decoder.h
@@ -2,8 +2,8 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#ifndef IOS_WEB_PUBLIC_WEBP_DECODER_H_
-#define IOS_WEB_PUBLIC_WEBP_DECODER_H_
+#ifndef COMPONENTS_WEBP_TRANSCODE_WEBP_DECODER_H_
+#define COMPONENTS_WEBP_TRANSCODE_WEBP_DECODER_H_
 
 #include "base/mac/scoped_nsobject.h"
 #include "base/memory/ref_counted.h"
@@ -12,7 +12,7 @@
 
 @class NSData;
 
-namespace web {
+namespace webp_transcode {
 
 // Decodes a WebP image into either JPEG, PNG or uncompressed TIFF.
 class WebpDecoder : public base::RefCountedThreadSafe<WebpDecoder> {
@@ -20,12 +20,7 @@ class WebpDecoder : public base::RefCountedThreadSafe<WebpDecoder> {
   // Format of the decoded image.
   // This enum is used for UMA reporting, keep it in sync with the histogram
   // definition.
-  enum DecodedImageFormat {
-    JPEG = 1,
-    PNG,
-    TIFF,
-    DECODED_FORMAT_COUNT
-  };
+  enum DecodedImageFormat { JPEG = 1, PNG, TIFF, DECODED_FORMAT_COUNT };
 
   class Delegate : public base::RefCountedThreadSafe<WebpDecoder::Delegate> {
    public:
@@ -55,11 +50,7 @@ class WebpDecoder : public base::RefCountedThreadSafe<WebpDecoder> {
     inline void operator()(WebPIDecoder* ptr) const { WebPIDelete(ptr); }
   };
 
-  enum State {
-    READING_FEATURES,
-    READING_DATA,
-    DONE
-  };
+  enum State { READING_FEATURES, READING_DATA, DONE };
 
   friend class base::RefCountedThreadSafe<WebpDecoder>;
   virtual ~WebpDecoder();
@@ -78,6 +69,6 @@ class WebpDecoder : public base::RefCountedThreadSafe<WebpDecoder> {
   int has_alpha_;
 };
 
-}  // namespace web
+}  // namespace webp_transcode
 
-#endif  // IOS_WEB_PUBLIC_WEBP_DECODER_H_
+#endif  // COMPONENTS_WEBP_TRANSCODE_WEBP_DECODER_H_
diff --git a/ios/web/public/webp_decoder.mm b/components/webp_transcode/webp_decoder.mm
index 3ac1cda..05c834b 100644
--- a/ios/web/public/webp_decoder.mm
+++ b/components/webp_transcode/webp_decoder.mm
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "ios/web/public/webp_decoder.h"
+#include "components/webp_transcode/webp_decoder.h"
 
 #import <Foundation/Foundation.h>
 #import <UIKit/UIKit.h>
@@ -37,8 +37,8 @@ void WriteTiffHeader(uint8_t* dst,
                      int bytes_per_px,
                      bool has_alpha) {
   // For non-alpha case, we omit tag 0x152 (ExtraSamples).
-  const uint8_t num_ifd_entries = has_alpha ? kNumIfdEntries
-                                            : kNumIfdEntries - 1;
+  const uint8_t num_ifd_entries =
+      has_alpha ? kNumIfdEntries : kNumIfdEntries - 1;
   uint8_t tiff_header[kHeaderSize] = {
     0x49, 0x49, 0x2a, 0x00,   // little endian signature
     8, 0, 0, 0,               // offset to the unique IFD that follows
@@ -83,7 +83,7 @@ void WriteTiffHeader(uint8_t* dst,
 
 }  // namespace
 
-namespace web {
+namespace webp_transcode {
 
 // static
 size_t WebpDecoder::GetHeaderSize() {
@@ -184,9 +184,9 @@ void WebpDecoder::DoReadData(NSData* data) {
   DCHECK_EQ(READING_DATA, state_);
   DCHECK(incremental_decoder_);
   DCHECK(data);
-  VP8StatusCode status = WebPIAppend(incremental_decoder_.get(),
-                                     static_cast<const uint8_t*>([data bytes]),
-                                     [data length]);
+  VP8StatusCode status =
+      WebPIAppend(incremental_decoder_.get(),
+                  static_cast<const uint8_t*>([data bytes]), [data length]);
   switch (status) {
     case VP8_STATUS_SUSPENDED:
       // Do nothing: re-compression to JPEG or PNG cannot be done incrementally.
@@ -210,8 +210,8 @@ void WebpDecoder::DoReadData(NSData* data) {
 bool WebpDecoder::DoSendData() {
   DCHECK_EQ(READING_DATA, state_);
   int width, height;
-  uint8_t* data_ptr =
-      WebPIDecGetRGB(incremental_decoder_.get(), NULL, &width, &height, NULL);
+  uint8_t* data_ptr = WebPIDecGetRGB(incremental_decoder_.get(), nullptr,
+                                     &width, &height, nullptr);
   if (!data_ptr)
     return false;
   DCHECK_EQ(static_cast<const uint8_t*>([output_buffer_ bytes]) + kHeaderSize,
@@ -240,12 +240,12 @@ bool WebpDecoder::DoSendData() {
   } else {
     result_data.reset([output_buffer_ retain]);
   }
-  UMA_HISTOGRAM_ENUMERATION(
-      "WebP.DecodedImageFormat", format, DECODED_FORMAT_COUNT);
+  UMA_HISTOGRAM_ENUMERATION("WebP.DecodedImageFormat", format,
+                            DECODED_FORMAT_COUNT);
   delegate_->SetImageFeatures([result_data length], format);
   delegate_->OnDataDecoded(result_data);
   output_buffer_.reset();
   return true;
 }
 
-}  // namespace web
+}  // namespace webp_transcode
diff --git a/ios/web/public/webp_decoder_unittest.mm b/components/webp_transcode/webp_decoder_unittest.mm
index 40d20a1..5130ca7 100644
--- a/ios/web/public/webp_decoder_unittest.mm
+++ b/components/webp_transcode/webp_decoder_unittest.mm
@@ -2,7 +2,7 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "ios/web/public/webp_decoder.h"
+#include "components/webp_transcode/webp_decoder.h"
 
 #import <CoreGraphics/CoreGraphics.h>
 #import <Foundation/Foundation.h>
@@ -18,13 +18,12 @@
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
 
-namespace web {
+namespace webp_transcode {
 namespace {
 
 class WebpDecoderDelegate : public WebpDecoder::Delegate {
  public:
-  WebpDecoderDelegate() : image_([[NSMutableData alloc] init]) {
-  }
+  WebpDecoderDelegate() : image_([[NSMutableData alloc] init]) {}
 
   NSData* GetImage() const { return image_; }
 
@@ -32,7 +31,7 @@ class WebpDecoderDelegate : public WebpDecoder::Delegate {
   MOCK_METHOD1(OnFinishedDecoding, void(bool success));
   MOCK_METHOD2(SetImageFeatures,
                void(size_t total_size, WebpDecoder::DecodedImageFormat format));
-  virtual void OnDataDecoded(NSData* data) { [image_ appendData:data]; }
+  void OnDataDecoded(NSData* data) override { [image_ appendData:data]; }
 
  private:
   virtual ~WebpDecoderDelegate() {}
@@ -49,7 +48,8 @@ class WebpDecoderTest : public testing::Test {
   NSData* LoadImage(const base::FilePath& filename) {
     base::FilePath path;
     PathService::Get(base::DIR_SOURCE_ROOT, &path);
-    path = path.AppendASCII("ios/web/test/data").Append(filename);
+    path = path.AppendASCII("components/test/data/webp_transcode")
+               .Append(filename);
     return
         [NSData dataWithContentsOfFile:base::SysUTF8ToNSString(path.value())];
   }
@@ -62,11 +62,11 @@ class WebpDecoderTest : public testing::Test {
     switch (format) {
       case WebpDecoder::JPEG:
         image.reset(CGImageCreateWithJPEGDataProvider(
-            provider, NULL, false, kCGRenderingIntentDefault));
+            provider, nullptr, false, kCGRenderingIntentDefault));
         break;
       case WebpDecoder::PNG:
         image.reset(CGImageCreateWithPNGDataProvider(
-            provider, NULL, false, kCGRenderingIntentDefault));
+            provider, nullptr, false, kCGRenderingIntentDefault));
         break;
       case WebpDecoder::TIFF:
         ADD_FAILURE() << "Data already decompressed";
@@ -115,9 +115,9 @@ class WebpDecoderTest : public testing::Test {
   bool CheckCompressedImagesEqual(NSData* data_1,
                                   NSData* data_2,
                                   WebpDecoder::DecodedImageFormat format) {
-    scoped_ptr<std::vector<uint8_t> > uncompressed_1(
+    scoped_ptr<std::vector<uint8_t>> uncompressed_1(
         DecompressData(data_1, format));
-    scoped_ptr<std::vector<uint8_t> > uncompressed_2(
+    scoped_ptr<std::vector<uint8_t>> uncompressed_2(
         DecompressData(data_2, format));
     if (uncompressed_1->size() != uncompressed_2->size()) {
       DLOG(ERROR) << "Image sizes don't match";
@@ -167,8 +167,8 @@ TEST_F(WebpDecoderTest, DecodeToJpeg) {
   ASSERT_TRUE(jpg_image != nil);
   // Convert to JPEG.
   EXPECT_CALL(*delegate_, OnFinishedDecoding(true)).Times(1);
-  EXPECT_CALL(*delegate_,
-              SetImageFeatures(testing::_, WebpDecoder::JPEG)).Times(1);
+  EXPECT_CALL(*delegate_, SetImageFeatures(testing::_, WebpDecoder::JPEG))
+      .Times(1);
   decoder_->OnDataReceived(webp_image);
   // Compare to reference image.
   EXPECT_TRUE(CheckCompressedImagesEqual(jpg_image, delegate_->GetImage(),
@@ -186,8 +186,8 @@ TEST_F(WebpDecoderTest, DecodeToPng) {
   ASSERT_TRUE(png_image != nil);
   // Convert to PNG.
   EXPECT_CALL(*delegate_, OnFinishedDecoding(true)).Times(1);
-  EXPECT_CALL(*delegate_,
-              SetImageFeatures(testing::_, WebpDecoder::PNG)).Times(1);
+  EXPECT_CALL(*delegate_, SetImageFeatures(testing::_, WebpDecoder::PNG))
+      .Times(1);
   decoder_->OnDataReceived(webp_image);
   // Compare to reference image.
   EXPECT_TRUE(CheckCompressedImagesEqual(png_image, delegate_->GetImage(),
@@ -223,16 +223,17 @@ TEST_F(WebpDecoderTest, StreamedDecode) {
   ASSERT_TRUE(jpg_image != nil);
   // Convert to JPEG in chunks.
   EXPECT_CALL(*delegate_, OnFinishedDecoding(true)).Times(1);
-  EXPECT_CALL(*delegate_,
-              SetImageFeatures(testing::_, WebpDecoder::JPEG)).Times(1);
+  EXPECT_CALL(*delegate_, SetImageFeatures(testing::_, WebpDecoder::JPEG))
+      .Times(1);
   const size_t kChunkSize = 10;
   unsigned int num_chunks = 0;
   while ([webp_image length] > kChunkSize) {
     base::scoped_nsobject<NSData> chunk(
         [[webp_image subdataWithRange:NSMakeRange(0, kChunkSize)] retain]);
     decoder_->OnDataReceived(chunk);
-    webp_image.reset([[webp_image subdataWithRange:NSMakeRange(
-        kChunkSize, [webp_image length] - kChunkSize)] retain]);
+    webp_image.reset([[webp_image
+        subdataWithRange:NSMakeRange(kChunkSize, [webp_image length] -
+                                                     kChunkSize)] retain]);
     ++num_chunks;
   }
   if ([webp_image length] > 0u) {
@@ -260,4 +261,4 @@ TEST_F(WebpDecoderTest, DecodeAborted) {
   EXPECT_EQ(0u, [delegate_->GetImage() length]);
 }
 
-}  // namespace web
+}  // namespace webp_transcode
diff --git a/ios/chrome/DEPS b/ios/chrome/DEPS
index fb23515..e6bb4b0 100644
--- a/ios/chrome/DEPS
+++ b/ios/chrome/DEPS
@@ -5,6 +5,7 @@ include_rules = [
   "+components/leveldb_proto",
   "+components/suggestions",
   "+components/translate/core",
+  "+components/webp_transcode",
   "+ios/public/provider/chrome",
   "+ios/web/public",
   "+net",
diff --git a/ios/chrome/browser/net/image_fetcher.mm b/ios/chrome/browser/net/image_fetcher.mm
index bff9639..2d45c01 100644
--- a/ios/chrome/browser/net/image_fetcher.mm
+++ b/ios/chrome/browser/net/image_fetcher.mm
@@ -10,8 +10,8 @@
 #include "base/location.h"
 #include "base/mac/scoped_nsobject.h"
 #include "base/task_runner.h"
+#include "components/webp_transcode/webp_decoder.h"
 #include "ios/web/public/web_thread.h"
-#include "ios/web/public/webp_decoder.h"
 #include "net/base/load_flags.h"
 #include "net/http/http_response_headers.h"
 #include "net/url_request/url_fetcher.h"
@@ -19,7 +19,7 @@
 
 namespace {
 
-class WebpDecoderDelegate : public web::WebpDecoder::Delegate {
+class WebpDecoderDelegate : public webp_transcode::WebpDecoder::Delegate {
  public:
   NSData* data() const { return decoded_image_; }
 
@@ -30,7 +30,7 @@ class WebpDecoderDelegate : public web::WebpDecoder::Delegate {
   }
   void SetImageFeatures(
       size_t total_size,
-      web::WebpDecoder::DecodedImageFormat format) override {
+      webp_transcode::WebpDecoder::DecodedImageFormat format) override {
     decoded_image_.reset([[NSMutableData alloc] initWithCapacity:total_size]);
   }
   void OnDataDecoded(NSData* data) override {
@@ -50,7 +50,8 @@ static const char kWEBPMimeType[] = "image/webp";
 base::scoped_nsobject<NSData> DecodeWebpImage(
     const base::scoped_nsobject<NSData>& webp_image) {
   scoped_refptr<WebpDecoderDelegate> delegate(new WebpDecoderDelegate);
-  scoped_refptr<web::WebpDecoder> decoder(new web::WebpDecoder(delegate.get()));
+  scoped_refptr<webp_transcode::WebpDecoder> decoder(
+      new webp_transcode::WebpDecoder(delegate.get()));
   decoder->OnDataReceived(webp_image);
   DLOG_IF(ERROR, !delegate->data()) << "WebP image decoding failed.";
   return base::scoped_nsobject<NSData>([delegate->data() retain]);
diff --git a/ios/chrome/ios_chrome.gyp b/ios/chrome/ios_chrome.gyp
index 0174556..fe3e2db 100644
--- a/ios/chrome/ios_chrome.gyp
+++ b/ios/chrome/ios_chrome.gyp
@@ -21,6 +21,7 @@
         '../../components/components.gyp:leveldb_proto',
         '../../components/components.gyp:suggestions',
         '../../components/components.gyp:translate_core_browser',
+        '../../components/components.gyp:webp_transcode',
         '../../net/net.gyp:net',
         '../../skia/skia.gyp:skia',
         '../../url/url.gyp:url_lib',
diff --git a/ios/ios_tests_unit.gyp b/ios/ios_tests_unit.gyp
index 64da0d6..3d33685 100644
--- a/ios/ios_tests_unit.gyp
+++ b/ios/ios_tests_unit.gyp
@@ -22,27 +22,9 @@
       'sources': [
         'web/browser_state_unittest.cc',
         'web/navigation/navigation_item_impl_unittest.mm',
-        'web/public/webp_decoder_unittest.mm',
         'web/string_util_unittest.cc',
         'web/url_scheme_util_unittest.mm',
       ],
-      'actions': [
-        {
-          'action_name': 'copy_test_data',
-          'variables': {
-            'test_data_files': [
-              'web/test/data/test.jpg',
-              'web/test/data/test.webp',
-              'web/test/data/test_alpha.webp',
-              'web/test/data/test_alpha.png',
-              'web/test/data/test_small.tiff',
-              'web/test/data/test_small.webp',
-            ],
-            'test_data_prefix': 'ios',
-          },
-          'includes': [ '../build/copy_test_data_ios.gypi' ],
-        },
-      ],
     },
   ],
 }
diff --git a/ios/web/ios_web.gyp b/ios/web/ios_web.gyp
index d256398..72833e8 100644
--- a/ios/web/ios_web.gyp
+++ b/ios/web/ios_web.gyp
@@ -14,7 +14,6 @@
         '../..',
       ],
       'dependencies': [
-        'webp_decoder',
         '../../base/base.gyp:base',
         '../../content/content.gyp:content_browser',
         '../../net/net.gyp:net',
@@ -88,21 +87,6 @@
       ],
     },
     {
-      'target_name': 'webp_decoder',
-      'type': 'static_library',
-      'include_dirs': [
-        '../..',
-      ],
-      'dependencies': [
-        '../../base/base.gyp:base',
-        '../../third_party/libwebp/libwebp.gyp:libwebp_dec',
-      ],
-      'sources': [
-        'public/webp_decoder.h',
-        'public/webp_decoder.mm',
-      ],
-    },
-    {
       'target_name': 'test_support_ios_web',
       'type': 'static_library',
       'dependencies': [