Revert of Large wallpaper decoding in utility process (patchset #5 id:190001 of https://codereview.chromium.org/482163002/)

Reason for revert:
Speculative revert for unit_tests failures:

http://build.chromium.org/p/chromium.chromiumos/builders/Linux%20ChromiumOS%20Tests%20%28dbg%29%281%29/builds/31845/steps/unit_tests/logs/DecodeImageSizeLimit

Original issue's description:
> Handle large wallpaper decoding in utility process:
> Images over 32M pixels exceed IPC message limit size.  In ChromeContentUtilityClient::DecodeImage(), cut image dimensions in half to minimize quality loss and allow decoded image to be returned via IPC message.
>
> BUG=366825
> TEST=ChromeContentUtilityClientTest.DecodeImageSizeLimit; Set ChromeOS wallpaper using JPGs attached to bug
>
> Committed: https://crrev.com/d9d0e601c4c45ec8f2fb1d148e68458d9baa4e24
> Cr-Commit-Position: refs/heads/master@{#296407}

TBR=dcheng@chromium.org,bshe@chromium.org,skuhne@chromium.org,sky@chromium.org,tsepez@chromium.org,yoz@chromium.org,glevin@chromium.org
NOTREECHECKS=true
NOTRY=true
BUG=366825

Review URL: https://codereview.chromium.org/600913002

Cr-Commit-Position: refs/heads/master@{#296457}

4 files changed, 10 insertions, 122 deletions

diff --git a/chrome/utility/chrome_content_utility_client.cc b/chrome/utility/chrome_content_utility_client.cc
index 990717a..d2c9b4a 100644
--- a/chrome/utility/chrome_content_utility_client.cc
+++ b/chrome/utility/chrome_content_utility_client.cc
@@ -18,8 +18,6 @@
 #include "content/public/utility/utility_thread.h"
 #include "courgette/courgette.h"
 #include "courgette/third_party/bsdiff.h"
-#include "ipc/ipc_channel.h"
-#include "skia/ext/image_operations.h"
 #include "third_party/skia/include/core/SkBitmap.h"
 #include "third_party/zlib/google/zip.h"
 #include "ui/gfx/codec/jpeg_codec.h"
@@ -175,43 +173,11 @@ void ChromeContentUtilityClient::PreSandboxStartup() {
 }
 
 // static
-SkBitmap ChromeContentUtilityClient::DecodeImage(
-    const std::vector<unsigned char>& encoded_data, bool shrink_to_fit) {
-  SkBitmap decoded_image = content::DecodeImage(&encoded_data[0],
-                                                gfx::Size(),
-                                                encoded_data.size());
-
-  int64_t max_msg_size = IPC::Channel::kMaximumMessageSize;
-  int64_t struct_size = sizeof(ChromeUtilityHostMsg_DecodeImage_Succeeded);
-  int64_t image_size = decoded_image.computeSize64();
-  int halves = 0;
-  while (struct_size + (image_size >> 2*halves) > max_msg_size)
-    halves++;
-  if (halves) {
-    if (shrink_to_fit) {
-      // If decoded image is too large for IPC message, shrink it by halves.
-      // This prevents quality loss, and should never overshrink on displays
-      // smaller than 3600x2400.
-      // TODO (Issue 416916): Instead of shrinking, return via shared memory
-      decoded_image = skia::ImageOperations::Resize(
-          decoded_image, skia::ImageOperations::RESIZE_LANCZOS3,
-          decoded_image.width() >> halves, decoded_image.height() >> halves);
-    } else {
-      // Image too big for IPC message, but caller didn't request resize;
-      // pre-delete image so DecodeImageAndSend() will send an error.
-      decoded_image.reset();
-      LOG(ERROR) << "Decoded image too large for IPC message";
-    }
-  }
-
-  return decoded_image;
-}
-
-// static
-void ChromeContentUtilityClient::DecodeImageAndSend(
-    const std::vector<unsigned char>& encoded_data, bool shrink_to_fit){
-  SkBitmap decoded_image = DecodeImage(encoded_data, shrink_to_fit);
-
+void ChromeContentUtilityClient::DecodeImage(
+    const std::vector<unsigned char>& encoded_data) {
+  const SkBitmap& decoded_image = content::DecodeImage(&encoded_data[0],
+                                                       gfx::Size(),
+                                                       encoded_data.size());
   if (decoded_image.empty()) {
     Send(new ChromeUtilityHostMsg_DecodeImage_Failed());
   } else {
@@ -238,8 +204,8 @@ void ChromeContentUtilityClient::OnUnpackWebResource(
 }
 
 void ChromeContentUtilityClient::OnDecodeImage(
-    const std::vector<unsigned char>& encoded_data, bool shrink_to_fit) {
-  DecodeImageAndSend(encoded_data, shrink_to_fit);
+    const std::vector<unsigned char>& encoded_data) {
+  DecodeImage(encoded_data);
 }
 
 #if defined(OS_CHROMEOS)
diff --git a/chrome/utility/chrome_content_utility_client.h b/chrome/utility/chrome_content_utility_client.h
index 8c3aae0..e701064 100644
--- a/chrome/utility/chrome_content_utility_client.h
+++ b/chrome/utility/chrome_content_utility_client.h
@@ -32,16 +32,12 @@ class ChromeContentUtilityClient : public content::ContentUtilityClient {
   static void PreSandboxStartup();
 
   // Shared with extensions::ExtensionsHandler.
-  static SkBitmap DecodeImage(const std::vector<unsigned char>& encoded_data,
-                              bool shrink_to_fit);
-  static void DecodeImageAndSend(const std::vector<unsigned char>& encoded_data,
-                                 bool shrink_to_fit);
+  static void DecodeImage(const std::vector<unsigned char>& encoded_data);
 
  private:
   // IPC message handlers.
   void OnUnpackWebResource(const std::string& resource_data);
-  void OnDecodeImage(const std::vector<unsigned char>& encoded_data,
-                     bool shrink_to_fit);
+  void OnDecodeImage(const std::vector<unsigned char>& encoded_data);
   void OnRobustJPEGDecodeImage(
       const std::vector<unsigned char>& encoded_data);
 
diff --git a/chrome/utility/chrome_content_utility_client_unittest.cc b/chrome/utility/chrome_content_utility_client_unittest.cc
deleted file mode 100644
index 7a8b560..0000000
--- a/chrome/utility/chrome_content_utility_client_unittest.cc
+++ /dev/null
@@ -1,74 +0,0 @@
-// Copyright 2014 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.
-
-#include "chrome/common/chrome_utility_messages.h"
-#include "chrome/utility/chrome_content_utility_client.h"
-#include "ipc/ipc_channel.h"
-#include "testing/gtest/include/gtest/gtest.h"
-#include "ui/gfx/codec/jpeg_codec.h"
-
-namespace {
-
-bool CreateJPEGImage(int width,
-                     int height,
-                     SkColor color,
-                     std::vector<unsigned char>* output) {
-  SkBitmap bitmap;
-  bitmap.allocN32Pixels(width, height);
-  bitmap.eraseColor(color);
-
-  const int kQuality = 50;
-  if (!gfx::JPEGCodec::Encode(
-          static_cast<const unsigned char*>(bitmap.getPixels()),
-          gfx::JPEGCodec::FORMAT_SkBitmap,
-          width,
-          height,
-          bitmap.rowBytes(),
-          kQuality,
-          output)) {
-    LOG(ERROR) << "Unable to encode " << width << "x" << height << " bitmap";
-    return false;
-  }
-  return true;
-}
-
-}  // namespace
-
-typedef testing::Test ChromeContentUtilityClientTest;
-
-// Test that DecodeImage() doesn't return image message > kMaximumMessageSize
-TEST_F(ChromeContentUtilityClientTest, DecodeImageSizeLimit) {
-  // Approx max height for 3:2 image that will fit in IPC message;
-  // 1.5 for width/height ratio, 4 for bytes/pixel
-  int max_height_for_msg = sqrt(IPC::Channel::kMaximumMessageSize/(1.5*4));
-  int base_msg_size = sizeof(ChromeUtilityHostMsg_DecodeImage_Succeeded);
-
-  // Sizes which should trigger dimension-halving 0, 1 and 2 times
-  int heights[] = { max_height_for_msg - 20,
-                    max_height_for_msg + 20,
-                    2 * max_height_for_msg + 20 };
-  int widths[] = { heights[0] * 3 / 2, heights[1] * 3 / 2, heights[2] * 3 / 2 };
-  for (size_t i = 0; i < arraysize(heights); i++) {
-    std::vector<unsigned char> jpg;
-    CreateJPEGImage(widths[i], heights[i], SK_ColorRED, &jpg);
-    SkBitmap bitmap = ChromeContentUtilityClient::DecodeImage(jpg, true);
-
-    // Check that image has been shrunk appropriately
-    EXPECT_LT(bitmap.computeSize64() + base_msg_size,
-              static_cast<int64_t>(IPC::Channel::kMaximumMessageSize));
-    // Android does its own image shrinking for memory conservation deeper in
-    // the decode, so more specific tests here won't work.
-#if !defined(OS_ANDROID)
-    EXPECT_EQ(widths[i] >> i, bitmap.width());
-    EXPECT_EQ(heights[i] >> i, bitmap.height());
-
-    // Check that if resize not requested and image exceeds IPC size limit,
-    // an empty image is returned
-    if (heights[i] > max_height_for_msg) {
-      SkBitmap empty_bmp = ChromeContentUtilityClient::DecodeImage(jpg, false);
-      EXPECT_TRUE(empty_bmp.empty());
-    }
-#endif
-  }
-}
diff --git a/chrome/utility/extensions/extensions_handler.cc b/chrome/utility/extensions/extensions_handler.cc
index 63ffcd1..e8ef09f 100644
--- a/chrome/utility/extensions/extensions_handler.cc
+++ b/chrome/utility/extensions/extensions_handler.cc
@@ -182,7 +182,7 @@ void ExtensionsHandler::OnDecodeImageBase64(
     decoded_vector[i] = static_cast<unsigned char>(decoded_string[i]);
   }
 
-  ChromeContentUtilityClient::DecodeImageAndSend(decoded_vector, false);
+  ChromeContentUtilityClient::DecodeImage(decoded_vector);
 }
 
 void ExtensionsHandler::OnParseJSON(const std::string& json) {