WebApp: Extract BookmarkAppHelper's gfx stuff into a separate file.

Extract all the low-level skia/gfx/color_util stuff as
ResizeIconsAndGenerateMissing function.

This is a cut-and-paste CL, no behavior changes.

Notes:
- WebApplicationInfo::IconInfo becomes IconInfo. TODO for next CL:
Merge IconInfo and BitmapAndSource - they are essentially the same.

- BookmarkAppHelperExtensionServiceTest.LinkedAppIconsAreNotChanged test
was always broken (a bug in ValidateAllIconsWithURLsArePresent helper)
https://codereview.chromium.org/1066623008/patch/80001/90005

This is a re-land of:
https://chromium-review.googlesource.com/c/chromium/src/+/1166751
MSan issue solved, ouput parameters initialized everywhere:
SkColor generated_icon_color = SK_ColorTRANSPARENT;

TBR=ortuno@chromium.org

Bug: 860581
Change-Id: Ib26c765083e67e3a1c938a49994a5f5d5ecc8265
Reviewed-on: https://chromium-review.googlesource.com/1170665
Commit-Queue: Alexey Baskakov <loyso@chromium.org>
Reviewed-by: Giovanni Ortuño Urquidi <ortuno@chromium.org>
Reviewed-by: Dominick Ng <dominickn@chromium.org>
Cr-Commit-Position: refs/heads/master@{#582491}

chrome/browser/extensions/bookmark_app_helper.h

@@ -15,6 +15,7 @@
 #include "base/memory/ref_counted.h"
 #include "base/memory/weak_ptr.h"
 #include "chrome/browser/installable/installable_metrics.h"
+#include "chrome/browser/web_applications/components/web_app_icon_generator.h"
 #include "chrome/common/web_application_info.h"
 #include "content/public/browser/notification_observer.h"
 #include "content/public/browser/notification_registrar.h"
@@ -45,15 +46,6 @@ class BookmarkAppHelper : public content::NotificationObserver {
     kUnknown,
   };
 
-  struct BitmapAndSource {
-    BitmapAndSource();
-    BitmapAndSource(const GURL& source_url_p, const SkBitmap& bitmap_p);
-    ~BitmapAndSource();
-
-    GURL source_url;
-    SkBitmap bitmap;
-  };
-
   typedef base::Callback<void(const Extension*, const WebApplicationInfo&)>
       CreateBookmarkAppCallback;
 
@@ -75,24 +67,10 @@ class BookmarkAppHelper : public content::NotificationObserver {
                                            WebApplicationInfo* web_app_info,
                                            ForInstallableSite installable_site);
 
-  // This finds the closest not-smaller bitmap in |bitmaps| for each size in
-  // |sizes| and resizes it to that size. This returns a map of sizes to bitmaps
-  // which contains only bitmaps of a size in |sizes| and at most one bitmap of
-  // each size.
-  static std::map<int, BitmapAndSource> ConstrainBitmapsToSizes(
-      const std::vector<BitmapAndSource>& bitmaps,
-      const std::set<int>& sizes);
-
   // Adds a square container icon of |output_size| and 2 * |output_size| pixels
   // to |bitmaps| by drawing the given |letter| into a rounded background of
   // |color|. For each size, if an icon of the requested size already exists in
-  // |bitmaps|, nothing will happen.
-  static void GenerateIcon(std::map<int, BitmapAndSource>* bitmaps,
-                           int output_size,
-                           SkColor color,
-                           char letter);
-
-  // Same as above, but the generated icon is returned in a
+  // |bitmaps|, nothing will happen. The generated icon is returned in a
   // `WebApplicationInfo::IconInfo`.
   static WebApplicationInfo::IconInfo GenerateIconInfo(int output_size,
                                                        SkColor color,
@@ -105,8 +83,8 @@ class BookmarkAppHelper : public content::NotificationObserver {
 
   // Resize icons to the accepted sizes, and generate any that are missing. Does
   // not update |web_app_info| except to update |generated_icon_color|.
-  static std::map<int, BitmapAndSource> ResizeIconsAndGenerateMissing(
-      std::vector<BitmapAndSource> icons,
+  static std::map<int, web_app::BitmapAndSource> ResizeIconsAndGenerateMissing(
+      std::vector<web_app::BitmapAndSource> icons,
       std::set<int> sizes_to_generate,
       WebApplicationInfo* web_app_info);
 
@@ -118,7 +96,7 @@ class BookmarkAppHelper : public content::NotificationObserver {
   // |bitmap_map| that has a URL and size matching that in |web_app_info|, as
   // well as adding any new images from |bitmap_map| that have no URL.
   static void UpdateWebAppIconsWithoutChangingLinks(
-      std::map<int, BookmarkAppHelper::BitmapAndSource> bitmap_map,
+      std::map<int, web_app::BitmapAndSource> bitmap_map,
       WebApplicationInfo* web_app_info);
 
   // Begins the asynchronous bookmark app creation.

chrome/browser/web_applications/components/BUILD.gn

@@ -8,6 +8,8 @@ source_set("components") {
     "pending_app_manager.h",
     "web_app_helpers.cc",
     "web_app_helpers.h",
+    "web_app_icon_generator.cc",
+    "web_app_icon_generator.h",
     "web_app_shortcut.cc",
     "web_app_shortcut.h",
     "web_app_shortcut_chromeos.cc",
@@ -49,6 +51,7 @@ source_set("unit_tests") {
   sources = [
     "web_app_helpers_unittest.cc",
     "web_app_icon_downloader_unittest.cc",
+    "web_app_icon_generator_unittest.cc",
     "web_app_shortcut_mac_unittest.mm",
     "web_app_shortcut_unittest.cc",
   ]

chrome/browser/web_applications/components/web_app_icon_generator.cc

+// Copyright 2018 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/browser/web_applications/components/web_app_icon_generator.h"
+
+#include <cctype>
+#include <string>
+#include <utility>
+
+#include "base/macros.h"
+#include "build/build_config.h"
+#include "chrome/grit/platform_locale_settings.h"
+#include "net/base/registry_controlled_domains/registry_controlled_domain.h"
+#include "skia/ext/image_operations.h"
+#include "ui/base/l10n/l10n_util.h"
+#include "ui/gfx/canvas.h"
+#include "ui/gfx/color_analysis.h"
+#include "ui/gfx/color_utils.h"
+#include "ui/gfx/font.h"
+#include "ui/gfx/font_list.h"
+#include "ui/gfx/geometry/rect.h"
+#include "ui/gfx/image/canvas_image_source.h"
+#include "ui/gfx/image/image.h"
+
+namespace web_app {
+
+namespace {
+
+// Generates a square container icon of |output_size| by drawing the given
+// |letter| into a rounded background of |color|.
+class GeneratedIconImageSource : public gfx::CanvasImageSource {
+ public:
+  explicit GeneratedIconImageSource(char letter, SkColor color, int output_size)
+      : gfx::CanvasImageSource(gfx::Size(output_size, output_size), false),
+        letter_(letter),
+        color_(color),
+        output_size_(output_size) {}
+  ~GeneratedIconImageSource() override {}
+
+ private:
+  // gfx::CanvasImageSource overrides:
+  void Draw(gfx::Canvas* canvas) override {
+    const uint8_t kLumaThreshold = 190;
+    const int icon_size = output_size_ * 3 / 4;
+    const int icon_inset = output_size_ / 8;
+    const size_t border_radius = output_size_ / 16;
+    const size_t font_size = output_size_ * 7 / 16;
+
+    std::string font_name =
+        l10n_util::GetStringUTF8(IDS_SANS_SERIF_FONT_FAMILY);
+#if defined(OS_CHROMEOS)
+    const std::string kChromeOSFontFamily = "Noto Sans";
+    font_name = kChromeOSFontFamily;
+#endif
+
+    // Draw a rounded rect of the given |color|.
+    cc::PaintFlags background_flags;
+    background_flags.setAntiAlias(true);
+    background_flags.setColor(color_);
+
+    gfx::Rect icon_rect(icon_inset, icon_inset, icon_size, icon_size);
+    canvas->DrawRoundRect(icon_rect, border_radius, background_flags);
+
+    // The text rect's size needs to be odd to center the text correctly.
+    gfx::Rect text_rect(icon_inset, icon_inset, icon_size + 1, icon_size + 1);
+    // Draw the letter onto the rounded rect. The letter's color depends on the
+    // luma of |color|.
+    const uint8_t luma = color_utils::GetLuma(color_);
+    canvas->DrawStringRectWithFlags(
+        base::string16(1, std::toupper(letter_)),
+        gfx::FontList(gfx::Font(font_name, font_size)),
+        (luma > kLumaThreshold) ? SK_ColorBLACK : SK_ColorWHITE, text_rect,
+        gfx::Canvas::TEXT_ALIGN_CENTER);
+  }
+
+  char letter_;
+
+  SkColor color_;
+
+  int output_size_;
+
+  DISALLOW_COPY_AND_ASSIGN(GeneratedIconImageSource);
+};
+
+// Adds a square container icon of |output_size| and 2 * |output_size| pixels
+// to |bitmaps| by drawing the given |letter| into a rounded background of
+// |color|. For each size, if an icon of the requested size already exists in
+// |bitmaps|, nothing will happen.
+void GenerateIcon(std::map<int, BitmapAndSource>* bitmaps,
+                  int output_size,
+                  SkColor color,
+                  char letter) {
+  // Do nothing if there is already an icon of |output_size|.
+  if (bitmaps->count(output_size))
+    return;
+
+  (*bitmaps)[output_size].bitmap = GenerateBitmap(output_size, color, letter);
+}
+
+void GenerateIcons(std::set<int> generate_sizes,
+                   const GURL& app_url,
+                   SkColor generated_icon_color,
+                   std::map<int, BitmapAndSource>* bitmap_map) {
+  // The letter that will be painted on the generated icon.
+  char icon_letter = ' ';
+  std::string domain_and_registry(
+      net::registry_controlled_domains::GetDomainAndRegistry(
+          app_url,
+          net::registry_controlled_domains::INCLUDE_PRIVATE_REGISTRIES));
+  if (!domain_and_registry.empty()) {
+    icon_letter = domain_and_registry[0];
+  } else if (app_url.has_host()) {
+    icon_letter = app_url.host_piece()[0];
+  }
+
+  // If no color has been specified, use a dark gray so it will stand out on the
+  // black shelf.
+  if (generated_icon_color == SK_ColorTRANSPARENT)
+    generated_icon_color = SK_ColorDKGRAY;
+
+  for (int size : generate_sizes) {
+    GenerateIcon(bitmap_map, size, generated_icon_color, icon_letter);
+  }
+}
+
+}  // namespace
+
+BitmapAndSource::BitmapAndSource() {}
+
+BitmapAndSource::BitmapAndSource(const GURL& source_url_p,
+                                 const SkBitmap& bitmap_p)
+    : source_url(source_url_p), bitmap(bitmap_p) {}
+
+BitmapAndSource::~BitmapAndSource() {}
+
+std::map<int, BitmapAndSource> ConstrainBitmapsToSizes(
+    const std::vector<BitmapAndSource>& bitmaps,
+    const std::set<int>& sizes) {
+  std::map<int, BitmapAndSource> output_bitmaps;
+  std::map<int, BitmapAndSource> ordered_bitmaps;
+  for (const BitmapAndSource& bitmap_and_source : bitmaps) {
+    const SkBitmap& bitmap = bitmap_and_source.bitmap;
+    DCHECK(bitmap.width() == bitmap.height());
+    ordered_bitmaps[bitmap.width()] = bitmap_and_source;
+  }
+
+  if (ordered_bitmaps.size() > 0) {
+    for (const auto& size : sizes) {
+      // Find the closest not-smaller bitmap, or failing that use the largest
+      // icon available.
+      auto bitmaps_it = ordered_bitmaps.lower_bound(size);
+      if (bitmaps_it != ordered_bitmaps.end())
+        output_bitmaps[size] = bitmaps_it->second;
+      else
+        output_bitmaps[size] = ordered_bitmaps.rbegin()->second;
+
+      // Resize the bitmap if it does not exactly match the desired size.
+      if (output_bitmaps[size].bitmap.width() != size) {
+        output_bitmaps[size].bitmap = skia::ImageOperations::Resize(
+            output_bitmaps[size].bitmap, skia::ImageOperations::RESIZE_LANCZOS3,
+            size, size);
+      }
+    }
+  }
+
+  return output_bitmaps;
+}
+
+SkBitmap GenerateBitmap(int output_size, SkColor color, char letter) {
+  gfx::ImageSkia icon_image(
+      std::make_unique<GeneratedIconImageSource>(letter, color, output_size),
+      gfx::Size(output_size, output_size));
+  SkBitmap dst;
+  if (dst.tryAllocPixels(icon_image.bitmap()->info())) {
+    icon_image.bitmap()->readPixels(dst.info(), dst.getPixels(), dst.rowBytes(),
+                                    0, 0);
+  }
+  return dst;
+}
+
+std::map<int, BitmapAndSource> ResizeIconsAndGenerateMissing(
+    const std::vector<BitmapAndSource>& icons,
+    const std::set<int>& sizes_to_generate,
+    const GURL& app_url,
+    SkColor* generated_icon_color) {
+  DCHECK(generated_icon_color);
+
+  // Resize provided icons to make sure we have versions for each size in
+  // |sizes_to_generate|.
+  std::map<int, BitmapAndSource> resized_bitmaps(
+      ConstrainBitmapsToSizes(icons, sizes_to_generate));
+
+  // Also add all provided icon sizes.
+  for (const BitmapAndSource& icon : icons) {
+    if (resized_bitmaps.find(icon.bitmap.width()) == resized_bitmaps.end())
+      resized_bitmaps.insert(std::make_pair(icon.bitmap.width(), icon));
+  }
+
+  // Determine the color that will be used for the icon's background. For this
+  // the dominant color of the first icon found is used.
+  if (resized_bitmaps.size()) {
+    color_utils::GridSampler sampler;
+    *generated_icon_color = color_utils::CalculateKMeanColorOfBitmap(
+        resized_bitmaps.begin()->second.bitmap);
+  }
+
+  // Work out what icons we need to generate here. Icons are only generated if
+  // there is no icon in the required size.
+  std::set<int> generate_sizes;
+  for (int size : sizes_to_generate) {
+    if (resized_bitmaps.find(size) == resized_bitmaps.end())
+      generate_sizes.insert(size);
+  }
+  GenerateIcons(generate_sizes, app_url, *generated_icon_color,
+                &resized_bitmaps);
+
+  return resized_bitmaps;
+}
+
+}  // namespace web_app

chrome/browser/web_applications/components/web_app_icon_generator.h

+// Copyright 2018 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.
+
+#ifndef CHROME_BROWSER_WEB_APPLICATIONS_COMPONENTS_WEB_APP_ICON_GENERATOR_H_
+#define CHROME_BROWSER_WEB_APPLICATIONS_COMPONENTS_WEB_APP_ICON_GENERATOR_H_
+
+#include <map>
+#include <set>
+#include <vector>
+
+#include "third_party/skia/include/core/SkBitmap.h"
+#include "third_party/skia/include/core/SkColor.h"
+#include "url/gurl.h"
+
+namespace web_app {
+
+struct BitmapAndSource {
+  BitmapAndSource();
+  BitmapAndSource(const GURL& source_url_p, const SkBitmap& bitmap_p);
+  ~BitmapAndSource();
+
+  GURL source_url;
+  SkBitmap bitmap;
+};
+
+// This finds the closest not-smaller bitmap in |bitmaps| for each size in
+// |sizes| and resizes it to that size. This returns a map of sizes to bitmaps
+// which contains only bitmaps of a size in |sizes| and at most one bitmap of
+// each size.
+std::map<int, BitmapAndSource> ConstrainBitmapsToSizes(
+    const std::vector<BitmapAndSource>& bitmaps,
+    const std::set<int>& sizes);
+
+// Generates a square container icon of |output_size| by drawing the given
+// |letter| into a rounded background of |color|.
+SkBitmap GenerateBitmap(int output_size, SkColor color, char letter);
+
+// Resize icons to the accepted sizes, and generate any that are missing.
+// Note that |app_url| is the launch URL for the app.
+// Output: |generated_icon_color| is the color to use if an icon needs to be
+// generated for the web app.
+std::map<int, BitmapAndSource> ResizeIconsAndGenerateMissing(
+    const std::vector<BitmapAndSource>& icons,
+    const std::set<int>& sizes_to_generate,
+    const GURL& app_url,
+    SkColor* generated_icon_color);
+
+}  // namespace web_app
+
+#endif  // CHROME_BROWSER_WEB_APPLICATIONS_COMPONENTS_WEB_APP_ICON_GENERATOR_H_