Update from https://crrev.com/317530

third_party/ots/docs/HowToTest.md

Index: third_party/ots/docs/HowToTest.md
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+Prerequisites
+=============
+
+You can use your Ubuntu box (>= 8.04. 9.10 is recommended) to test OTS library.
+
+First, install TrueType and OpenType fonts to the Ubuntu box as many as
+possible.
+
+    % sudo apt-get install ttf-.*[^0]$
+
+Then, put malicious TrueType fonts on `~/malicious/`. For details, please check
+http://code.google.com/p/chromium/issues/detail?id=27139#c2. Currently access
+to the issue is limited to chromium-security team members for security reasons.
+
+    % cd
+    % tar xjf ~/ttf-testsuite.tar.bz2
+
+Test
+====
+
+In order to verify that:
+
+1. OTS does not reject these unmalicious fonts.
+2. and transcoded fonts OTS generates can be loaded by a system font renderer (FreeType2).
+
+Run `test_unmalicious_fonts.sh` script:
+
+    % cd /path/to/ots/tests
+    % ./test_unmalicious_fonts.sh
+    ...............................................  (verify that no FAIL: is displayed)
+
+Then in order to verify that:
+
+1. OTS can reject malicious fonts
+2. or transcoded fonts generated by OTS do not crash a system font renderer (FreeType2).
+
+Run `test_malicious_fonts.sh` script:
+
+    % cd /path/to/ots/tests
+    % ./test_malicious_fonts.sh
+    ...............................................  (verify that no FAIL: is displayed)
+
+Command line tools
+==================
+
+We have some command line tools for tests. To build them:
+
+- On Linux:
+
+        % gyp --depth=. -f make ots-standalone.gyp
+        % make
+        (tool is located at build/Default directory)
+
+- On Windows (VC++ is needed):
+
+        % gyp --depth=. -f msvs ots-standalone.gyp
+        % devenv.exe /build Default ots-standalone.sln /project idempotent.vcproj
+        (tool is located at Default directory)
+
+- On Mac (XCode is needed):
+
+        % gyp --depth=. -f xcode ots-standalone.gyp
+        % xcodebuild -configuration Default -project ots-standalone.xcodeproj -target All
+        (tool is located at build/Default directory)
+
+You can use `idempotent` tool to check whether a font will be rejected or not.
+You can also use `ot-sanitise` tool to get sanitised font (it is available on
+Linux for now). See README file in the test directory for more details.