Use new getFontFamilyForCharacters() API.

content/common/child_process_sandbox_support_impl_linux.h

Index: content/common/child_process_sandbox_support_impl_linux.h
diff --git a/content/common/child_process_sandbox_support_impl_linux.h b/content/common/child_process_sandbox_support_impl_linux.h
index b26634a0d74d67ca609f3fe3e5526e7c146ee934..29b103ba75b8ac49cd4e923caf044ec9aaabf1d5 100644
--- a/content/common/child_process_sandbox_support_impl_linux.h
+++ b/content/common/child_process_sandbox_support_impl_linux.h
@@ -9,6 +9,7 @@
 #include "content/public/common/child_process_sandbox_support_linux.h"
 
 namespace WebKit {
+struct WebFontFamily;
 struct WebFontRenderStyle;
 }
 
@@ -20,11 +21,12 @@ namespace content {
 //   num_utf16: the number of 16-bit words in |utf16|
 //   preferred_locale: preferred locale identifier for the |utf16|
 //
-// Returns: the font family or an empty string if the request could not be
-// satisfied.
-std::string GetFontFamilyForCharacters(const uint16_t* utf16,
-                                       size_t num_utf16,
-                                       const char* preferred_locale);
+// Returns: a font family instance.
+// The instance has an empty font name if the request could not be satisfied.
+void GetFontFamilyForCharacters(const uint16_t* utf16,
+                                size_t num_utf16,
+                                const char* preferred_locale,
+                                WebKit::WebFontFamily* family);
 
 void GetRenderStyleForStrike(const char* family, int sizeAndStyle,
                              WebKit::WebFontRenderStyle* out);