am: Deglobalize software keyboard applet

src/common/string_util.cpp

@@ -214,13 +214,13 @@ std::string StringFromFixedZeroTerminatedBuffer(const char* buffer, std::size_t
     return std::string(buffer, len);
 }
 
-std::u16string UTF16StringFromFixedZeroTerminatedBuffer(const char16_t* buffer,
+std::u16string UTF16StringFromFixedZeroTerminatedBuffer(std::u16string_view buffer,
                                                         std::size_t max_len) {
     std::size_t len = 0;
     while (len < max_len && buffer[len] != '\0')
         ++len;
 
-    return std::u16string(buffer, len);
+    return std::u16string(buffer.begin(), buffer.begin() + len);
 }
 
 const char* TrimSourcePath(const char* path, const char* root) {