enable -Wstring-conversion when compiling with clang

Summary of try run with flag enabled as warning:

On linux_clang, there's false positives from a bunch of assert usage that does !"string" or "string" for a true or false value. It's only in third_party (Mesa, skia, libjingle, etc.) so it probably wouldn't be too hard to disable the warnings in those subtrees.

It diagnoses 4 useful locations:

1.
../../base/debug/trace_event_unittest.cc:70:41: warning: implicit conversion turns string literal into bool: 'const char [2]' to 'bool' [-Wstring-conversion]
    TraceLog::GetInstance()->SetEnabled("*");
    ~~~~~~~~                            ^~~

2.
../../sync/syncable/entry_kernel.cc:77:38: warning: implicit conversion turns string literal into bool: 'const char [5]' to 'bool' [-Wstring-conversion]
      value->SetBoolean("encrypted", "true");
      ~~~~~                          ^~~~~~

3.
../../chrome/browser/webdata/web_data_service.cc:334:17: warning: implicit conversion turns string literal into bool: 'const char [44]' to 'bool' [-Wstring-conversion]
    DLOG_ASSERT("WebDataService dtor called without Shutdown");
    ~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
../../base/logging.h:595:43: note: expanded from macro 'DLOG_ASSERT'

4.
../../chrome/browser/renderer_host/web_cache_manager_unittest.cc:259:20: warning: implicit conversion turns string literal into bool: 'const char [29]' to 'bool' [-Wstring-conversion]
      EXPECT_FALSE("Unexpected entry in strategy");
      ~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~


Finding #1 is what made me look into this, #3 and #4 are not doing what they're supposed to, and #2 is kind of funny so not all is lost.

So, 3 bugs and 1 very-close-to-a-bug: seems worth enabling.

R=thakis@chromium.org
TBR=darin@chromium.org, dhollowa@chromium.org, brettw@chromium.org, zea@chromium.org
BUG=177306

Review URL: https://chromiumcodereview.appspot.com/12258039

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@183998 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 1 insertions, 1 deletions

diff --git a/sync/syncable/entry_kernel.cc b/sync/syncable/entry_kernel.cc
index b8ac824..5b21612 100644
--- a/sync/syncable/entry_kernel.cc
+++ b/sync/syncable/entry_kernel.cc
@@ -74,7 +74,7 @@ void SetEncryptableProtoValues(
         cryptographer->CanDecrypt(encrypted) &&
         cryptographer->Decrypt(encrypted, &decrypted)) {
       value = EntitySpecificsToValue(decrypted);
-      value->SetBoolean("encrypted", "true");
+      value->SetBoolean("encrypted", true);
     } else {
       value = EntitySpecificsToValue(kernel.ref(field));
     }