When input is "" (or " " with trim_whitespace true), SplitString() should return an empty vector, not a vector of one empty string.

Brett and I discussed this for a while and felt this would be wise, whereas dropping all empty segments entirely (e.g. converting "a,,b" to a vector of two elements instead of three) was probably unwise. 

This also simplifies the code some. 

Fixing this also required changing the code in mime_util.cc to handle empty vectors to "are codecs valid" oracle functions (in which case we return false). I also fixed some style issues there. It also required avoiding passing the empty string in a test in extension_api_unittest.cc; Aaron assures me that this code is not expected to be defensive against such inputs, but at his suggestion I also added some CHECK()s to the API.

BUG=none
TEST=none
Review URL: https://chromiumcodereview.appspot.com/9960004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@129998 0039d316-1c4b-4281-b951-d872f2087c98

2 files changed, 2 insertions, 1 deletions

diff --git a/chrome/common/extensions/api/extension_api.cc b/chrome/common/extensions/api/extension_api.cc
index 6bbd8df..3178975 100644
--- a/chrome/common/extensions/api/extension_api.cc
+++ b/chrome/common/extensions/api/extension_api.cc
@@ -268,10 +268,12 @@ bool ExtensionAPI::IsPrivileged(const std::string& full_name) {
     std::vector<std::string> split;
     base::SplitString(full_name, '.', &split);
     std::reverse(split.begin(), split.end());
+    CHECK(!split.empty());  // |full_name| was empty or only whitespace.
 
     api_name = split.back();
     split.pop_back();
     if (api_name == "experimental") {
+      CHECK(!split.empty());  // |full_name| was "experimental" alone.
       api_name += "." + split.back();
       split.pop_back();
     }
diff --git a/chrome/common/extensions/api/extension_api_unittest.cc b/chrome/common/extensions/api/extension_api_unittest.cc
index bf240e1..1c5a22e3 100644
--- a/chrome/common/extensions/api/extension_api_unittest.cc
+++ b/chrome/common/extensions/api/extension_api_unittest.cc
@@ -26,7 +26,6 @@ TEST(ExtensionAPI, IsPrivileged) {
   EXPECT_TRUE(extension_api.IsPrivileged("extension.lastError"));
 
   // Default unknown names to privileged for paranoia's sake.
-  EXPECT_TRUE(extension_api.IsPrivileged(""));
   EXPECT_TRUE(extension_api.IsPrivileged("<unknown-namespace>"));
   EXPECT_TRUE(extension_api.IsPrivileged("extension.<unknown-member>"));