Convert remaining StringToLowerASCII to ToLowerASCII.

Remove StringToLowerASCII. This removes the template and makes a consistent call that can take a string piece.

http_response_headers.cc in HttpResponseHeaders::RemoveHeaderLine there seemed to be a bug where it did
  std::string old_header_name_lowercase(name);
where it actually meant
  std::string old_header_name_lowercase(old_header_name);
I fixed this.

There were a number of cases where url.host() or url.scheme() was passed to ToLowerASCII. These are already guaranteed lower-case, so I removed the call.

There were a number of cases in net that did return ToLowerASCII().c_str() when the return type is a std::string, which is unnecessary and wasteful. I removed the c_str() call.

NOPRESUBMIT=true
(for touching code with wstrings)

Review URL: https://codereview.chromium.org/1282363003

Cr-Commit-Position: refs/heads/master@{#342869}

4 files changed, 5 insertions, 6 deletions

diff --git a/components/mime_util/mime_util.cc b/components/mime_util/mime_util.cc
index 6c51a9e..fa7471b 100644
--- a/components/mime_util/mime_util.cc
+++ b/components/mime_util/mime_util.cc
@@ -155,7 +155,7 @@ bool MimeUtil::IsSupportedImageMimeType(const std::string& mime_type) const {
 }
 
 bool MimeUtil::IsSupportedNonImageMimeType(const std::string& mime_type) const {
-  return non_image_types_.find(base::StringToLowerASCII(mime_type)) !=
+  return non_image_types_.find(base::ToLowerASCII(mime_type)) !=
              non_image_types_.end() ||
 #if !defined(OS_IOS)
          media::IsSupportedMediaMimeType(mime_type) ||
@@ -169,7 +169,7 @@ bool MimeUtil::IsSupportedNonImageMimeType(const std::string& mime_type) const {
 }
 
 bool MimeUtil::IsUnsupportedTextMimeType(const std::string& mime_type) const {
-  return unsupported_text_types_.find(base::StringToLowerASCII(mime_type)) !=
+  return unsupported_text_types_.find(base::ToLowerASCII(mime_type)) !=
          unsupported_text_types_.end();
 }
 
diff --git a/components/storage_monitor/portable_device_watcher_win.cc b/components/storage_monitor/portable_device_watcher_win.cc
index 0d2e5a8..b57f80a 100644
--- a/components/storage_monitor/portable_device_watcher_win.cc
+++ b/components/storage_monitor/portable_device_watcher_win.cc
@@ -60,7 +60,7 @@ base::string16 GetPnpDeviceId(LPARAM data) {
     return base::string16();
   base::string16 device_id(dev_interface->dbcc_name);
   DCHECK(base::IsStringASCII(device_id));
-  return base::StringToLowerASCII(device_id);
+  return base::ToLowerASCII(device_id);
 }
 
 // Gets the friendly name of the device specified by the |pnp_device_id|. On
diff --git a/components/update_client/utils.cc b/components/update_client/utils.cc
index 11e8060..2b66050 100644
--- a/components/update_client/utils.cc
+++ b/components/update_client/utils.cc
@@ -188,7 +188,7 @@ bool DeleteFileAndEmptyParentDirectory(const base::FilePath& filepath) {
 std::string GetCrxComponentID(const CrxComponent& component) {
   const size_t kCrxIdSize = 16;
   CHECK_GE(component.pk_hash.size(), kCrxIdSize);
-  return HexStringToID(base::StringToLowerASCII(
+  return HexStringToID(base::ToLowerASCII(
       base::HexEncode(&component.pk_hash[0], kCrxIdSize)));
 }
 
diff --git a/components/url_matcher/regex_set_matcher.cc b/components/url_matcher/regex_set_matcher.cc
index 1b0b7f3..ae994db 100644
--- a/components/url_matcher/regex_set_matcher.cc
+++ b/components/url_matcher/regex_set_matcher.cc
@@ -47,8 +47,7 @@ bool RegexSetMatcher::Match(const std::string& text,
 
   // FilteredRE2 expects lowercase for prefiltering, but we still
   // match case-sensitively.
-  std::vector<RE2ID> atoms(FindSubstringMatches(
-      base::StringToLowerASCII(text)));
+  std::vector<RE2ID> atoms(FindSubstringMatches(base::ToLowerASCII(text)));
 
   std::vector<RE2ID> re2_ids;
   filtered_re2_->AllMatches(text, atoms, &re2_ids);