[ObjC] Use absl::StripAsciiWhitespace().

Dropping the custom impl that was used previously.

src/google/protobuf/compiler/objectivec/import_writer.cc

@@ -32,6 +32,7 @@
 #include "google/protobuf/compiler/objectivec/line_consumer.h"
 #include "google/protobuf/compiler/objectivec/names.h"
 #include "google/protobuf/io/printer.h"
+#include "absl/strings/ascii.h"
 
 // NOTE: src/google/protobuf/compiler/plugin.cc makes use of cerr for some
 // error cases, so it seems to be ok to use as a back door for errors.
@@ -63,9 +64,8 @@ bool ProtoFrameworkCollector::ConsumeLine(
         std::string(line) + "'.";
     return false;
   }
-  absl::string_view framework_name = line.substr(0, offset);
-  absl::string_view proto_file_list = line.substr(offset + 1);
-  TrimWhitespace(&framework_name);
+  absl::string_view framework_name = absl::StripAsciiWhitespace(line.substr(0, offset));
+  absl::string_view proto_file_list = absl::StripAsciiWhitespace(line.substr(offset + 1));
 
   int start = 0;
   while (start < proto_file_list.length()) {
@@ -74,8 +74,8 @@ bool ProtoFrameworkCollector::ConsumeLine(
       offset = proto_file_list.length();
     }
 
-    absl::string_view proto_file = proto_file_list.substr(start, offset - start);
-    TrimWhitespace(&proto_file);
+    absl::string_view proto_file =
+        absl::StripAsciiWhitespace(proto_file_list.substr(start, offset - start));
     if (!proto_file.empty()) {
       std::map<std::string, std::string>::iterator existing_entry =
           map_->find(std::string(proto_file));

src/google/protobuf/compiler/objectivec/line_consumer.cc

@@ -41,6 +41,7 @@
 #include <sstream>
 #include <vector>
 
+#include "absl/strings/ascii.h"
 #include "absl/strings/str_cat.h"
 #include "absl/strings/str_split.h"
 #include "google/protobuf/compiler/objectivec/line_consumer.h"
@@ -67,15 +68,6 @@ using ::open;
 
 namespace {
 
-void TrimWhitespace(absl::string_view* input) {
-  while (!input->empty() && absl::ascii_isspace(*input->data())) {
-    input->remove_prefix(1);
-  }
-  while (!input->empty() && absl::ascii_isspace((*input)[input->length() - 1])) {
-    input->remove_suffix(1);
-  }
-}
-
 bool ascii_isnewline(char c) {
   return c == '\n' || c == '\r';
 }
@@ -134,7 +126,7 @@ bool Parser::ParseChunk(absl::string_view chunk, std::string* out_error) {
   while (ReadLine(&full_chunk, &line)) {
     ++line_;
     RemoveComment(&line);
-    TrimWhitespace(&line);
+    line = absl::StripAsciiWhitespace(line);
     if (!line.empty() && !line_consumer_->ConsumeLine(line, out_error)) {
       if (out_error->empty()) {
         *out_error = "ConsumeLine failed without setting an error.";

src/google/protobuf/compiler/objectivec/names.cc

@@ -36,6 +36,7 @@
 #include <vector>
 
 #include "google/protobuf/compiler/code_generator.h"
+#include "absl/strings/ascii.h"
 #include "absl/strings/str_split.h"
 #include "google/protobuf/compiler/objectivec/line_consumer.h"
 #include "google/protobuf/compiler/objectivec/names.h"
@@ -497,15 +498,6 @@ void MaybeUnQuote(absl::string_view* input) {
 
 }  // namespace
 
-void TrimWhitespace(absl::string_view* input) {
-  while (!input->empty() && absl::ascii_isspace(*input->data())) {
-    input->remove_prefix(1);
-  }
-  while (!input->empty() && absl::ascii_isspace((*input)[input->length() - 1])) {
-    input->remove_suffix(1);
-  }
-}
-
 bool IsRetainedName(const std::string& name) {
   // List of prefixes from
   // http://developer.apple.com/library/mac/#documentation/Cocoa/Conceptual/MemoryMgmt/Articles/mmRules.html
@@ -865,10 +857,8 @@ bool PackageToPrefixesCollector::ConsumeLine(
     *out_error = usage_ + " file line without equal sign: '" + absl::StrCat(line) + "'.";
     return false;
   }
-  absl::string_view package = line.substr(0, offset);
-  absl::string_view prefix = line.substr(offset + 1);
-  TrimWhitespace(&package);
-  TrimWhitespace(&prefix);
+  absl::string_view package = absl::StripAsciiWhitespace(line.substr(0, offset));
+  absl::string_view prefix = absl::StripAsciiWhitespace(line.substr(offset + 1));
   MaybeUnQuote(&prefix);
   // Don't really worry about error checking the package/prefix for
   // being valid.  Assume the file is validated when it is created/edited.

src/google/protobuf/compiler/objectivec/names.h

@@ -69,9 +69,6 @@ void PROTOC_EXPORT SetProtoPackagePrefixExceptionList(
 std::string PROTOC_EXPORT GetForcedPackagePrefix();
 void PROTOC_EXPORT SetForcedPackagePrefix(const std::string& prefix);
 
-// Remove white space from either end of a absl::string_view.
-void PROTOC_EXPORT TrimWhitespace(absl::string_view* input);
-
 // Returns true if the name requires a ns_returns_not_retained attribute applied
 // to it.
 bool PROTOC_EXPORT IsRetainedName(const std::string& name);