Elide long emails in the wrench and profile menus.

ui/base/text/text_elider.cc

Index: ui/base/text/text_elider.cc
diff --git a/ui/base/text/text_elider.cc b/ui/base/text/text_elider.cc
index 525cea0df61eb373507b91372f144dbf327cf419..8ea7c09c4beb00f926a1e7e0a2b45f33b8194efb 100644
--- a/ui/base/text/text_elider.cc
+++ b/ui/base/text/text_elider.cc
@@ -35,6 +35,8 @@ namespace ui {
 const char kEllipsis[] = "\xE2\x80\xA6";
 const char16 kForwardSlash = '/';
 
+const size_t kMaxProfileUsernameLength = 20;
+
 namespace {
 
 // Helper class to split + elide text, while respecting UTF16 surrogate pairs.
@@ -149,6 +151,41 @@ string16 ElideComponentizedPath(const string16& url_path_prefix,
 
 }  // namespace
 
+string16 ElideEmail(const string16& email, size_t max_email_length) {
+  DCHECK_GE(max_email_length, 5U);
+
+  if (email.length() <= max_email_length)
+    return email;
+
+  std::vector<string16> email_split;
+  base::SplitString(email, '@', &email_split);
+  DCHECK_EQ(email_split.size(), 2U);
+  string16 username = email_split.front();
+  string16 domain = email_split.back();
+
+  const string16 kEllipsisUTF16 = UTF8ToUTF16(kEllipsis);
+  const size_t kEllipsisLength = kEllipsisUTF16.length();
+
+  // Reserve characters for each of: username ellipsis, @ sign, and at least
+  // one character remaining in the username.
+  const size_t available_domain_chars = max_email_length - kEllipsisLength - 2;
+  if (domain.length() > available_domain_chars) {
+    StringSlicer slicer(domain, kEllipsisUTF16, true);
+    const size_t length = max_email_length / 2 - kEllipsisLength;
+    domain = slicer.CutString(length, true);
+  }
+
+  const size_t final_domain_length = domain.length();
+  if (username.length() + final_domain_length + 1 > max_email_length) {
+    StringSlicer slicer(username, kEllipsisUTF16, false);
+    const size_t length = max_email_length - final_domain_length -
+                     kEllipsisLength - 1;
+    username = slicer.CutString(length, true);
+  }
+
+  return username + ASCIIToUTF16("@") + domain;
+}
+
 // This function takes a GURL object and elides it. It returns a string
 // which composed of parts from subdomain, domain, path, filename and query.
 // A "..." is added automatically at the end if the elided string is bigger