Fixing missed cache reads for table schema.

Because cache keys were different, model schema would not be read from
the cache.  Make keys used consistent.

Fixes #2670

lib/Cake/Model/Datasource/Database/Mysql.php

@@ -297,7 +297,8 @@ class Mysql extends DboSource {
  * @throws CakeException
  */
 	public function describe($model) {
-		$cache = parent::describe($model);
+		$key = $this->fullTableName($model, false);
+		$cache = parent::describe($key);
 		if ($cache != null) {
 			return $cache;
 		}
@@ -331,7 +332,7 @@ class Mysql extends DboSource {
 				}
 			}
 		}
-		$this->_cacheDescription($this->fullTableName($model, false), $fields);
+		$this->_cacheDescription($key, $fields);
 		$cols->closeCursor();
 		return $fields;
 	}

lib/Cake/Model/Datasource/Database/Postgres.php

@@ -186,8 +186,8 @@ class Postgres extends DboSource {
  * @return array Fields in table. Keys are name and type
  */
 	public function describe($model) {
-		$fields = parent::describe($model);
 		$table = $this->fullTableName($model, false, false);
+		$fields = parent::describe($table);
 		$this->_sequenceMap[$table] = array();
 		$cols = null;
 

lib/Cake/Model/Datasource/Database/Sqlite.php

@@ -160,11 +160,11 @@ class Sqlite extends DboSource {
  * @return array Fields in table. Keys are name and type
  */
 	public function describe($model) {
-		$cache = parent::describe($model);
+		$table = $this->fullTableName($model, false, false);
+		$cache = parent::describe($table);
 		if ($cache != null) {
 			return $cache;
 		}
-		$table = $this->fullTableName($model, false, false);
 		$fields = array();
 		$result = $this->_execute('PRAGMA table_info(' . $table . ')');
 

lib/Cake/Model/Datasource/Database/Sqlserver.php

@@ -201,7 +201,8 @@ class Sqlserver extends DboSource {
  * @throws CakeException
  */
 	public function describe($model) {
-		$cache = parent::describe($model);
+		$table = $this->fullTableName($model, false);
+		$cache = parent::describe($table);
 		if ($cache != null) {
 			return $cache;
 		}