build sql as a component - this will help ensure there is only one copy

sql/connection.h

Index: sql/connection.h
diff --git a/sql/connection.h b/sql/connection.h
index 5807e36361ff200445f2d5321d5350bd5d747a42..5446c0c67a927101ba081cf370e08f28209b21a2 100644
--- a/sql/connection.h
+++ b/sql/connection.h
@@ -13,6 +13,7 @@
 #include "base/basictypes.h"
 #include "base/memory/ref_counted.h"
 #include "base/time.h"
+#include "sql/sql_export.h"
 
 class FilePath;
 struct sqlite3;
@@ -76,7 +77,7 @@ class Connection;
 // the OnError() callback.
 // The tipical usage is to centralize the code designed to handle database
 // corruption, low-level IO errors or locking violations.
-class ErrorDelegate : public base::RefCounted<ErrorDelegate> {
+class SQL_EXPORT ErrorDelegate : public base::RefCounted<ErrorDelegate> {
  public:
   ErrorDelegate();
 
@@ -99,7 +100,7 @@ class ErrorDelegate : public base::RefCounted<ErrorDelegate> {
   virtual ~ErrorDelegate();
 };
 
-class Connection {
+class SQL_EXPORT Connection {
  private:
   class StatementRef;  // Forward declaration, see real one below.