Use global scope to find Error classes (thanks to @wr0ngway)

Change-Id: I6b9bb24d2bda03f298d3f67cb9ff0f9458713abe
Reviewed-on: http://review.couchbase.org/21362
Tested-by: Sergey Avseyev <sergey.avseyev@gmail.com>
Reviewed-by: Matt Ingenthron <matt@couchbase.com>
Reviewed-by: Chris Anderson <jchris@couchbase.com>

lib/active_support/cache/couchbase_store.rb

@@ -184,7 +184,7 @@ def read_multi(*names)
         instrument(:read_multi, names, options) do
           @data.get(names, options)
         end
-      rescue Couchbase::Error::Base => e
+      rescue ::Couchbase::Error::Base => e
         logger.error("#{e.class}: #{e.message}") if logger
         raise if @raise_errors
         false
@@ -245,7 +245,7 @@ def increment(name, amount = 1, options = nil)
           payload[:amount] = amount if payload
           @data.incr(name, amount, options)
         end
-      rescue Couchbase::Error::Base => e
+      rescue ::Couchbase::Error::Base => e
         logger.error("#{e.class}: #{e.message}") if logger
         raise if @raise_errors
         false
@@ -277,7 +277,7 @@ def decrement(name, amount = 1, options = nil)
           payload[:amount] = amount if payload
           @data.decr(name, amount, options)
         end
-      rescue Couchbase::Error::Base => e
+      rescue ::Couchbase::Error::Base => e
         logger.error("#{e.class}: #{e.message}") if logger
         raise if @raise_errors
         false
@@ -297,7 +297,7 @@ def stats(*arg)
       # Read an entry from the cache.
       def read_entry(key, options) # :nodoc:
         @data.get(key, options)
-      rescue Couchbase::Error::Base => e
+      rescue ::Couchbase::Error::Base => e
         logger.error("#{e.class}: #{e.message}") if logger
         raise if @raise_errors
         nil
@@ -314,7 +314,7 @@ def write_entry(key, value, options) # :nodoc:
           options[:ttl] ||= ttl
         end
         @data.send(method, key, value, options)
-      rescue Couchbase::Error::Base => e
+      rescue ::Couchbase::Error::Base => e
         logger.error("#{e.class}: #{e.message}") if logger
         raise if @raise_errors
         false
@@ -323,7 +323,7 @@ def write_entry(key, value, options) # :nodoc:
       # Delete an entry from the cache.
       def delete_entry(key, options) # :nodoc:
         @data.delete(key, options)
-      rescue Couchbase::Error::Base => e
+      rescue ::Couchbase::Error::Base => e
         logger.error("#{e.class}: #{e.message}") if logger
         raise if @raise_errors
         false

lib/rack/session/couchbase.rb

@@ -90,7 +90,7 @@ def destroy_session(env, session_id, options)
       def with_lock(env, default = nil)
         @mutex.lock if env['rack.multithread']
         yield
-      rescue Couchbase::Error::Connect, Couchbase::Error::Timeout
+      rescue ::Couchbase::Error::Connect, ::Couchbase::Error::Timeout
         if $VERBOSE
           warn "#{self} is unable to find Couchbase server."
           warn $!.inspect