Extension docs build script, gyp target and PRESUBMIT.PY check

chrome/common/extensions/docs/js/bootstrap.js

Index: chrome/common/extensions/docs/js/bootstrap.js
diff --git a/chrome/common/extensions/docs/js/bootstrap.js b/chrome/common/extensions/docs/js/bootstrap.js
new file mode 100755
index 0000000000000000000000000000000000000000..5282030de944b2098e62af0949345e2ca9aa3f71
--- /dev/null
+++ b/chrome/common/extensions/docs/js/bootstrap.js
@@ -0,0 +1,11 @@
+window.onload = function() {
+  // Regenerate page if we are passed the "?regenerate" search param
+  // or if the user-agent is chrome AND the document is being served
+  // from the file:/// scheme.
+  if (window.location.search == "?regenerate" ||
+      navigator.userAgent.indexOf("Chrome") > -1) {
+    // Hide body content initially to minimize flashing.
+    document.getElementsByTagName("body")[0].className = "hidden";
+    window.renderPage();
+  }
+}