mojo: Create a basic clipboard.

This creates a basic clipboard interface and uses it from
html_viewer. This is a minimal implementation and does not actually
interact with the system clipboard.

BUG=411039

Review URL: https://codereview.chromium.org/562483002

Cr-Commit-Position: refs/heads/master@{#295143}

3 files changed, 52 insertions, 0 deletions

diff --git a/mojo/common/common_type_converters.cc b/mojo/common/common_type_converters.cc
index ffc1907..114b409 100644
--- a/mojo/common/common_type_converters.cc
+++ b/mojo/common/common_type_converters.cc
@@ -46,4 +46,20 @@ GURL TypeConverter<GURL, String>::Convert(const String& input) {
   return GURL(input.get());
 }
 
+std::string TypeConverter<std::string, Array<uint8_t> >::Convert(
+    const Array<uint8_t>& input) {
+  if (input.is_null())
+    return std::string();
+
+  return std::string(reinterpret_cast<const char*>(&input.front()),
+                     input.size());
+}
+
+Array<uint8_t> TypeConverter<Array<uint8_t>, std::string>::Convert(
+    const std::string& input) {
+  Array<uint8_t> result(input.size());
+  memcpy(&result.front(), input.c_str(), input.size());
+  return result.Pass();
+}
+
 }  // namespace mojo
diff --git a/mojo/common/common_type_converters.h b/mojo/common/common_type_converters.h
index 159325e..7b0260a 100644
--- a/mojo/common/common_type_converters.h
+++ b/mojo/common/common_type_converters.h
@@ -8,6 +8,7 @@
 #include "base/strings/string16.h"
 #include "base/strings/string_piece.h"
 #include "mojo/common/mojo_common_export.h"
+#include "mojo/public/cpp/bindings/array.h"
 #include "mojo/public/cpp/bindings/string.h"
 #include "mojo/public/cpp/bindings/type_converter.h"
 
@@ -45,6 +46,20 @@ struct MOJO_COMMON_EXPORT TypeConverter<GURL, String> {
   static GURL Convert(const String& input);
 };
 
+// TODO(erg): In the very long term, we will want to remove conversion between
+// std::strings and arrays of unsigned bytes. However, there is too much code
+// across chrome which uses std::string as a bag of bytes that we probably
+// don't want to roll this function at each callsite.
+template <>
+struct MOJO_COMMON_EXPORT TypeConverter<std::string, Array<uint8_t> > {
+  static std::string Convert(const Array<uint8_t>& input);
+};
+
+template <>
+struct MOJO_COMMON_EXPORT TypeConverter<Array<uint8_t>, std::string> {
+  static Array<uint8_t> Convert(const std::string& input);
+};
+
 }  // namespace mojo
 
 #endif  // MOJO_COMMON_COMMON_TYPE_CONVERTERS_H_
diff --git a/mojo/common/common_type_converters_unittest.cc b/mojo/common/common_type_converters_unittest.cc
index 314f180..f97be0a 100644
--- a/mojo/common/common_type_converters_unittest.cc
+++ b/mojo/common/common_type_converters_unittest.cc
@@ -84,6 +84,27 @@ TEST(CommonTypeConvertersTest, URL) {
   ASSERT_EQ(0U, string_from_invalid.size());
 }
 
+TEST(CommonTypeConvertersTest, ArrayUint8ToStdString) {
+  Array<uint8_t> data(4);
+  data[0] = 'd';
+  data[1] = 'a';
+  data[2] = 't';
+  data[3] = 'a';
+
+  EXPECT_EQ("data", data.To<std::string>());
+}
+
+TEST(CommonTypeConvertersTest, StdStringToArrayUint8) {
+  std::string input("data");
+  Array<uint8_t> data = Array<uint8_t>::From(input);
+
+  ASSERT_EQ(4ul, data.size());
+  EXPECT_EQ('d', data[0]);
+  EXPECT_EQ('a', data[1]);
+  EXPECT_EQ('t', data[2]);
+  EXPECT_EQ('a', data[3]);
+}
+
 }  // namespace test
 }  // namespace common
 }  // namespace mojo