[Icons NTP] Add path_index() to ParsedFallbackIconPath.

Making ParsedFallbackIconPath resemble ParsedFaviconPath, to prepare it
for chrome-search:// URL with <view_id>/<restricted_id> . Details:
- Replacing url() with url_string(). Need to update chrome://large-icon
  endpoint and test to accommodate.
- Adding path_index().

BUG=467712

Review URL: https://codereview.chromium.org/1017803003

Cr-Commit-Position: refs/heads/master@{#321615}

chrome/browser/ui/webui/fallback_icon_source.cc

@@ -15,6 +15,7 @@
 #include "net/url_request/url_request.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "ui/gfx/favicon_size.h"
+#include "url/gurl.h"
 
 FallbackIconSource::FallbackIconSource() {
   std::vector<std::string> font_list;
@@ -47,8 +48,11 @@ void FallbackIconSource::StartDataRequest(
     SendDefaultResponse(callback);
     return;
   }
-
-  GURL url(parsed.url());
+  GURL url(parsed.url_string());
+  if (url.is_empty() || !url.is_valid()) {
+    SendDefaultResponse(callback);
+    return;
+  }
   std::vector<unsigned char> bitmap_data =
       fallback_icon_service_->RenderFallbackIconBitmap(
           url, parsed.size_in_pixels(), parsed.style());

chrome/common/favicon/fallback_icon_url_parser.cc

@@ -54,10 +54,15 @@ bool ParsedFallbackIconPath::Parse(const std::string& path) {
   if (!ParseSpecs(spec_str, &size_in_pixels_, &style_))
     return false;  // Parse failed.
 
-  // Extract URL, which may be empty (if first slash appears at the end).
-  std::string url_str = path.substr(slash + 1);
-  url_ = GURL(url_str);
-  return url_str.empty() || url_.is_valid();  // Allow empty URL.
+  // Need to store the index of the URL field, so Instant Extended can translate
+  // fallback icon URLs using advanced parameters.
+  // Example:
+  //   "chrome-search://fallback-icon/48/<renderer-id>/<most-visited-id>"
+  // would be translated to:
+  //   "chrome-search://fallback-icon/48/<most-visited-item-with-given-id>".
+  path_index_ = slash + 1;
+  url_string_ = path.substr(path_index_);
+  return true;
 }
 
 // static

chrome/common/favicon/fallback_icon_url_parser.h

@@ -11,7 +11,6 @@
 #include "base/macros.h"
 #include "components/favicon_base/fallback_icon_style.h"
 #include "third_party/skia/include/core/SkColor.h"
-#include "url/gurl.h"
 
 namespace chrome {
 
@@ -20,12 +19,14 @@ class ParsedFallbackIconPath {
   ParsedFallbackIconPath();
   ~ParsedFallbackIconPath();
 
-  const GURL& url() const { return url_; }
+  const std::string& url_string() const { return url_string_; }
 
   int size_in_pixels() const { return size_in_pixels_; }
 
   const favicon_base::FallbackIconStyle& style() const { return style_; }
 
+  size_t path_index() const { return path_index_; }
+
   // Parses |path|, which should be in the format described at the top of the
   // file "chrome/browser/ui/webui/fallback_icon_source.h".
   bool Parse(const std::string& path);
@@ -50,8 +51,8 @@ class ParsedFallbackIconPath {
   FRIEND_TEST_ALL_PREFIXES(FallbackIconUrlParserTest, ParseSpecsFull);
   FRIEND_TEST_ALL_PREFIXES(FallbackIconUrlParserTest, ParseSpecsFailure);
 
-  // The page URL the fallback icon is requested for.
-  GURL url_;
+  // The page URL string the fallback icon is requested for.
+  std::string url_string_;
 
   // The size of the requested fallback icon in pixels.
   int size_in_pixels_;
@@ -59,6 +60,10 @@ class ParsedFallbackIconPath {
   // Styling specifications of fallback icon.
   favicon_base::FallbackIconStyle style_;
 
+  // The index of the first character (relative to the path) where the the URL
+  // from which the fallback icon is being requested is located.
+  size_t path_index_;
+
   DISALLOW_COPY_AND_ASSIGN(ParsedFallbackIconPath);
 };
 

chrome/common/favicon/fallback_icon_url_parser_unittest.cc

@@ -213,39 +213,57 @@ TEST_F(FallbackIconUrlParserTest, ParseFallbackIconPathSuccess) {
   {
     chrome::ParsedFallbackIconPath parsed;
     EXPECT_TRUE(parsed.Parse(specs + "/" + kTestUrlStr));
-    EXPECT_EQ(GURL(kTestUrlStr), parsed.url());
     EXPECT_EQ(31, parsed.size_in_pixels());
     const favicon_base::FallbackIconStyle& style = parsed.style();
     EXPECT_EQ(SkColorSetRGB(0x00, 0x00, 0x00), style.background_color);
     EXPECT_EQ(SkColorSetRGB(0xFF, 0xFF, 0xFF), style.text_color);
     EXPECT_EQ(0.75, style.font_size_ratio);
     EXPECT_EQ(0.25, style.roundness);
+    EXPECT_EQ(GURL(kTestUrlStr), GURL(parsed.url_string()));
+    EXPECT_EQ(specs.length() + 1, parsed.path_index());
   }
 
   // Empty URL.
   {
     chrome::ParsedFallbackIconPath parsed;
     EXPECT_TRUE(parsed.Parse(specs + "/"));
-    EXPECT_EQ(GURL(), parsed.url());
     EXPECT_EQ(31, parsed.size_in_pixels());
     const favicon_base::FallbackIconStyle& style = parsed.style();
     EXPECT_EQ(SkColorSetRGB(0x00, 0x00, 0x00), style.background_color);
     EXPECT_EQ(SkColorSetRGB(0xFF, 0xFF, 0xFF), style.text_color);
     EXPECT_EQ(0.75, style.font_size_ratio);
     EXPECT_EQ(0.25, style.roundness);
+    EXPECT_EQ(GURL(), GURL(parsed.url_string()));
+    EXPECT_EQ(specs.length() + 1, parsed.path_index());
+  }
+
+  // Tolerate invalid URL.
+  {
+    chrome::ParsedFallbackIconPath parsed;
+    EXPECT_TRUE(parsed.Parse(specs + "/NOT A VALID URL"));
+    EXPECT_EQ(31, parsed.size_in_pixels());
+    const favicon_base::FallbackIconStyle& style = parsed.style();
+    EXPECT_EQ(SkColorSetRGB(0x00, 0x00, 0x00), style.background_color);
+    EXPECT_EQ(SkColorSetRGB(0xFF, 0xFF, 0xFF), style.text_color);
+    EXPECT_EQ(0.75, style.font_size_ratio);
+    EXPECT_EQ(0.25, style.roundness);
+    EXPECT_EQ("NOT A VALID URL", parsed.url_string());
+    EXPECT_EQ(specs.length() + 1, parsed.path_index());
   }
 
   // Size and style are default.
   {
+    std::string specs2 = ",,,,";
     chrome::ParsedFallbackIconPath parsed;
-    EXPECT_TRUE(parsed.Parse(std::string(",,,,/") + kTestUrlStr));
-    EXPECT_EQ(GURL(kTestUrlStr), parsed.url());
+    EXPECT_TRUE(parsed.Parse(specs2 + "/" + kTestUrlStr));
     EXPECT_EQ(gfx::kFaviconSize, parsed.size_in_pixels());
     const favicon_base::FallbackIconStyle& style = parsed.style();
     EXPECT_EQ(kDefaultBackgroundColor, style.background_color);
     EXPECT_EQ(kDefaultTextColorLight, style.text_color);
     EXPECT_EQ(kDefaultFontSizeRatio, style.font_size_ratio);
     EXPECT_EQ(kDefaultRoundness, style.roundness);
+    EXPECT_EQ(GURL(kTestUrlStr), GURL(parsed.url_string()));
+    EXPECT_EQ(specs2.length() + 1, parsed.path_index());
   }
 }
 
@@ -255,8 +273,6 @@ TEST_F(FallbackIconUrlParserTest, ParseFallbackIconPathFailure) {
     "-1,000,fff,0.75,0.25/http://www.google.com/",
     // Bad specs.
     "32,#junk,fff,0.75,0.25/http://www.google.com/",
-    // Bad URL.
-    "32,000,fff,0.75,0.25/NOT A VALID URL",
   };
   for (size_t i = 0; i < arraysize(test_cases); ++i) {
     chrome::ParsedFallbackIconPath parsed;