[Import Maps] Fix ImportMap::ToString()

Before this CL, strings are not escaped, which caused
test failures when strings in import maps contains e.g. backslashes.

This CL fixes the test failures by escaping the strings
using EncodeForDebugging().

This CL doesn't affect non-test behaviors because ToString()
is only used from test code.

Bug: 990561
Change-Id: I0b1b8dd428026c2c9c8a837022e1d2c71604113f
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1843314
Commit-Queue: Hiroshige Hayashizaki <hiroshige@chromium.org>
Reviewed-by: Kouhei Ueno <kouhei@chromium.org>
Cr-Commit-Position: refs/heads/master@{#703477}

third_party/blink/renderer/core/script/import_map.cc

@@ -576,17 +576,16 @@ String ImportMap::ToString() const {
     if (!is_first_key)
       builder.Append(",");
     is_first_key = false;
-    builder.Append("\n  \"");
-    builder.Append(it.key);
-    builder.Append("\": [");
+    builder.Append("\n  ");
+    builder.Append(it.key.EncodeForDebugging());
+    builder.Append(": [");
     bool is_first_value = true;
     for (const auto& v : it.value) {
       if (!is_first_value)
         builder.Append(",");
       is_first_value = false;
-      builder.Append("\n    \"");
-      builder.Append(v.GetString());
-      builder.Append("\"");
+      builder.Append("\n    ");
+      builder.Append(v.GetString().EncodeForDebugging());
     }
     builder.Append("\n  ]");
   }

third_party/blink/web_tests/external/wpt/import-maps/imported/parsing-addresses.tentative-expected.txt

@@ -5,7 +5,7 @@ PASS Relative URL-like addresses / should accept the literal strings ./, ../, or
 PASS Relative URL-like addresses / should ignore percent-encoded variants of ./, ../, or /
 PASS Built-in module addresses / should accept URLs using the built-in module scheme
 PASS Built-in module addresses / should ignore percent-encoded variants of the built-in module scheme
-FAIL Built-in module addresses / should allow built-in module URLs that contain "/" or "\" assert_equals: expected "{\"backslash\":[\"std:foo\\\baz\"],\"slashEnd\":[\"std:foo/\"],\"slashMiddle\":[\"std:foo/bar\"]}" but got "{\"backslash\":[\"std:foo\\baz\"],\"slashEnd\":[\"std:foo/\"],\"slashMiddle\":[\"std:foo/bar\"]}"
+PASS Built-in module addresses / should allow built-in module URLs that contain "/" or "\"
 FAIL Absolute URL addresses / should only accept absolute URL addresses with fetch schemes assert_equals: expected "{\"about\":[\"about:good\"],\"blob\":[\"blob:good\"],\"data\":[\"data:good\"],\"file\":[\"file:///good\"],\"filesystem\":[\"filesystem:good\"],\"ftp\":[\"ftp://good/\"],\"http\":[\"http://good/\"],\"https\":[\"https://good/\"],\"import\":[],\"javascript\":[],\"mailto\":[],\"wss\":[]}" but got "{\"about\":[\"about:good\"],\"blob\":[\"blob:good\"],\"data\":[\"data:good\"],\"file\":[\"file:///good\"],\"filesystem\":[],\"ftp\":[\"ftp://good/\"],\"http\":[\"http://good/\"],\"https\":[\"https://good/\"],\"import\":[\"import:bad\"],\"javascript\":[\"javascript:bad\"],\"mailto\":[\"mailto:bad\"],\"wss\":[\"wss://bad/\"]}"
 FAIL Absolute URL addresses / should only accept absolute URL addresses with fetch schemes inside arrays assert_equals: expected "{\"about\":[\"about:good\"],\"blob\":[\"blob:good\"],\"data\":[\"data:good\"],\"file\":[\"file:///good\"],\"filesystem\":[\"filesystem:good\"],\"ftp\":[\"ftp://good/\"],\"http\":[\"http://good/\"],\"https\":[\"https://good/\"],\"import\":[],\"javascript\":[],\"mailto\":[],\"wss\":[]}" but got "{\"about\":[\"about:good\"],\"blob\":[\"blob:good\"],\"data\":[\"data:good\"],\"file\":[\"file:///good\"],\"filesystem\":[],\"ftp\":[\"ftp://good/\"],\"http\":[\"http://good/\"],\"https\":[\"https://good/\"],\"import\":[\"import:bad\"],\"javascript\":[\"javascript:bad\"],\"mailto\":[\"mailto:bad\"],\"wss\":[\"wss://bad/\"]}"
 FAIL Absolute URL addresses / should parse absolute URLs, ignoring unparseable ones assert_equals: expected "{\"invalidButParseable1\":[\"https://example.org/\"],\"invalidButParseable2\":[\"https://example.com///\"],\"noPercentDecoding\":[\"https://example.com/%41\"],\"percentDecoding\":[\"https://example.com/\"],\"prettyNormal\":[\"https://example.net/\"],\"unparseable1\":[],\"unparseable2\":[],\"unparseable3\":[]}" but got "{\"invalidButParseable1\":[\"https://example.org/\"],\"invalidButParseable2\":[\"https://example.com///\"],\"noPercentDecoding\":[\"https://example.com/A\"],\"percentDecoding\":[\"https://example.com/\"],\"prettyNormal\":[\"https://example.net/\"],\"unparseable1\":[\"https://ex%20ample.org/\"],\"unparseable2\":[],\"unparseable3\":[]}"

third_party/blink/web_tests/external/wpt/import-maps/imported/parsing-specifier-keys.tentative-expected.txt

@@ -5,6 +5,6 @@ PASS Relative URL-like specifier keys / should absolutize the literal strings ./
 PASS Relative URL-like specifier keys / should treat percent-encoded variants of ./, ../, or / as bare specifiers
 FAIL Absolute URL specifier keys / should only accept absolute URL specifier keys with fetch schemes, treating others as bare specifiers assert_equals: expected "{\"about:good\":[\"https://base.example/about\"],\"blob:good\":[\"https://base.example/blob\"],\"data:good\":[\"https://base.example/data\"],\"file:///good\":[\"https://base.example/file\"],\"filesystem:good\":[\"https://base.example/filesystem\"],\"ftp://good/\":[\"https://base.example/ftp/\"],\"http://good/\":[\"https://base.example/http/\"],\"https://good/\":[\"https://base.example/https/\"],\"import:bad\":[\"https://base.example/import\"],\"javascript:bad\":[\"https://base.example/javascript\"],\"mailto:bad\":[\"https://base.example/mailto\"],\"wss:bad\":[\"https://base.example/wss\"]}" but got "{\"about:good\":[\"https://base.example/about\"],\"blob:good\":[\"https://base.example/blob\"],\"data:good\":[\"https://base.example/data\"],\"file:///good\":[\"https://base.example/file\"],\"filesystem:good\":[\"https://base.example/filesystem\"],\"ftp://good/\":[\"https://base.example/ftp/\"],\"http://good/\":[\"https://base.example/http/\"],\"https://good/\":[\"https://base.example/https/\"],\"import:bad\":[\"https://base.example/import\"],\"javascript:bad\":[\"https://base.example/javascript\"],\"mailto:bad\":[\"https://base.example/mailto\"],\"wss://bad/\":[\"https://base.example/wss\"]}"
 FAIL Absolute URL specifier keys / should parse absolute URLs, treating unparseable ones as bare specifiers assert_equals: expected "{\"http://[www.example.com]/\":[\"https://base.example/unparseable3/\"],\"https://ex ample.org/\":[\"https://base.example/unparseable1/\"],\"https://example.com/\":[\"https://base.example/percentDecoding/\"],\"https://example.com/%41\":[\"https://base.example/noPercentDecoding\"],\"https://example.com///\":[\"https://base.example/invalidButParseable2/\"],\"https://example.com:demo\":[\"https://base.example/unparseable2\"],\"https://example.net/\":[\"https://base.example/prettyNormal/\"],\"https://example.org/\":[\"https://base.example/invalidButParseable1/\"]}" but got "{\"http://[www.example.com]/\":[\"https://base.example/unparseable3/\"],\"https://ex%20ample.org/\":[\"https://base.example/unparseable1/\"],\"https://example.com/\":[\"https://base.example/percentDecoding/\"],\"https://example.com///\":[\"https://base.example/invalidButParseable2/\"],\"https://example.com/A\":[\"https://base.example/noPercentDecoding\"],\"https://example.com:demo\":[\"https://base.example/unparseable2\"],\"https://example.net/\":[\"https://base.example/prettyNormal/\"],\"https://example.org/\":[\"https://base.example/invalidButParseable1/\"]}"
-FAIL Absolute URL specifier keys / should parse built-in module specifier keys, including with a "/" assert_equals: expected "{\"std:blank\":[\"https://base.example/blank\"],\"std:blank/\":[\"https://base.example/blank/\"],\"std:blank/foo\":[\"https://base.example/blank/foo\"],\"std:blank\\\foo\":[\"https://base.example/blank/backslashfoo\"]}" but got "{\"std:blank\":[\"https://base.example/blank\"],\"std:blank\\foo\":[\"https://base.example/blank/backslashfoo\"],\"std:blank/\":[\"https://base.example/blank/\"],\"std:blank/foo\":[\"https://base.example/blank/foo\"]}"
+PASS Absolute URL specifier keys / should parse built-in module specifier keys, including with a "/"
 Harness: the test ran to completion.