Removed global $driver variable from WebElement.pm

This fixed two issues, one immediately apparent, the other not so much

1. because of this hanging reference the driver would be the last item
   to be destroyed on global destruction... the child remoteConnection
   and Commands instances were being destroyed first and therefore not
   available to the driver when calling quit().

2. This reference to the $driver would cause problems if you were ever
   to create multiple sessions in a single script.

lib/Selenium/Remote/WebElement.pm

@@ -4,10 +4,6 @@ use strict;
 use warnings;
 use Data::Dumper;
 
-# This is the already instantiated Driver object, which will be passed to the
-# constructor when this class is instantiated.
-my $driver;
-
 =head1 NAME
 
 Selenium::Remote::WebElement - Representation of an HTML Element used by Selenium Remote Driver
@@ -31,14 +27,19 @@ various element related operations can be carried out.
 
 sub new {
     my ($class, $id, $parent) = @_;
-    $driver = $parent;
     my $self = {
         id => $id,
+        driver => $parent,
     };
     bless $self, $class or die "Can't bless $class: $!";
     return $self;
 }
 
+sub _execute_command {
+    my ($self) = shift;
+    return $self->{driver}->_execute_command(@_);
+}
+
 =head2 click
 
  Description:
@@ -52,7 +53,7 @@ sub new {
 sub click {
     my ($self) = @_;
     my $res = { 'command' => 'clickElement', 'id' => $self->{id} };
-    return $driver->_execute_command($res);
+    return $self->_execute_command($res);
 }
 
 =head2 get_value
@@ -71,7 +72,7 @@ sub click {
 sub get_value {
     my ($self) = @_;
     my $res = { 'command' => 'getElementValue', 'id' => $self->{id} };
-    return $driver->_execute_command($res);
+    return $self->_execute_command($res);
 }
 
 =head2 submit
@@ -88,7 +89,7 @@ sub get_value {
 sub submit {
     my ($self) = @_;
     my $res = { 'command' => 'submitElement', 'id' => $self->{id} };
-    return $driver->_execute_command($res);
+    return $self->_execute_command($res);
 }
 
 =head2 send_keys
@@ -112,7 +113,7 @@ sub send_keys {
     my $params = {
         'value' => \@strings,
     };
-    return $driver->_execute_command($res, $params);
+    return $self->_execute_command($res, $params);
 }
 
 =head2 is_selected
@@ -132,7 +133,7 @@ sub send_keys {
 sub is_selected {
     my ($self) = @_;
     my $res = { 'command' => 'isElementSelected', 'id' => $self->{id} };
-    return $driver->_execute_command($res);
+    return $self->_execute_command($res);
 }
 
 =head2 set_selected
@@ -148,7 +149,7 @@ sub is_selected {
 sub set_selected {
     my ($self) = @_;
     my $res = { 'command' => 'setElementSelected', 'id' => $self->{id} };
-    return $driver->_execute_command($res);
+    return $self->_execute_command($res);
 }
 
 =head2 toggle
@@ -168,7 +169,7 @@ sub set_selected {
 sub toggle {
     my ($self) = @_;
     my $res = { 'command' => 'toggleElement', 'id' => $self->{id} };
-    return $driver->_execute_command($res);
+    return $self->_execute_command($res);
 }
 
 =head2 is_enabled
@@ -187,7 +188,7 @@ sub toggle {
 sub is_enabled {
     my ($self) = @_;
     my $res = { 'command' => 'isElementEnabled', 'id' => $self->{id} };
-    return $driver->_execute_command($res);
+    return $self->_execute_command($res);
 }
 
 =head2 get_element_location
@@ -207,7 +208,7 @@ sub is_enabled {
 sub get_element_location {
     my ($self) = @_;
     my $res = { 'command' => 'getElementLocation', 'id' => $self->{id} };
-    return $driver->_execute_command($res);
+    return $self->_execute_command($res);
 }
 
 =head2 get_element_location_in_view
@@ -230,7 +231,7 @@ sub get_element_location {
 sub get_element_location_in_view {
     my ($self) = @_;
     my $res = { 'command' => 'getElementLocationInView', 'id' => $self->{id} };
-    return $driver->_execute_command($res);
+    return $self->_execute_command($res);
 }
 
 =head2 get_tag_name
@@ -249,7 +250,7 @@ sub get_element_location_in_view {
 sub get_tag_name {
     my ($self) = @_;
     my $res = { 'command' => 'getElementTagName', 'id' => $self->{id} };
-    return $driver->_execute_command($res);
+    return $self->_execute_command($res);
 }
 
 =head2 clear
@@ -265,7 +266,7 @@ sub get_tag_name {
 sub clear {
     my ($self) = @_;
     my $res = { 'command' => 'clearElement', 'id' => $self->{id} };
-    return $driver->_execute_command($res);
+    return $self->_execute_command($res);
 }
 
 =head2 get_attribute
@@ -294,7 +295,7 @@ sub get_attribute {
                'id' => $self->{id},
                'name' => $attr_name,
                };
-    return $driver->_execute_command($res);
+    return $self->_execute_command($res);
 }
 
 =head2 is_displayed
@@ -313,7 +314,7 @@ sub get_attribute {
 sub is_displayed {
     my ($self) = @_;
     my $res = { 'command' => 'isElementDisplayed', 'id' => $self->{id} };
-    return $driver->_execute_command($res);
+    return $self->_execute_command($res);
 }
 
 =head2 drag
@@ -342,7 +343,7 @@ sub drag {
         'x' => $x,
         'y' => $y,
     };
-    return $driver->_execute_command($res, $params);
+    return $self->_execute_command($res, $params);
 }
 
 =head2 get_size
@@ -362,7 +363,7 @@ sub drag {
 sub get_size {
     my ($self) = @_;
     my $res = { 'command' => 'getElementSize', 'id' => $self->{id} };
-    return $driver->_execute_command($res);
+    return $self->_execute_command($res);
 }
 
 =head2 get_text
@@ -381,7 +382,7 @@ sub get_size {
 sub get_text {
     my ($self) = @_;
     my $res = { 'command' => 'getElementText', 'id' => $self->{id} };
-    return $driver->_execute_command($res);
+    return $self->_execute_command($res);
 }
 
 =head2 get_css_attribute
@@ -412,7 +413,7 @@ sub get_css_attribute {
                'id' => $self->{id},
                'property_name' => $attr_name,
                };
-    return $driver->_execute_command($res);
+    return $self->_execute_command($res);
 }
 
 =head2 hover
@@ -428,7 +429,7 @@ sub get_css_attribute {
 sub hover {
     my ($self) = @_;
     my $res = { 'command' => 'hoverOverElement', 'id' => $self->{id} };
-    return $driver->_execute_command($res);
+    return $self->_execute_command($res);
 }