Globally

• Download BetterTouchTool
• Drag it into your Applications folder and then double click the Application to start it.
• Select "Other" from the right side of the horizontal menu that is in black.
• Select "Global" from the left navigation.
• Select "Configure New Trigger" from the bottom of the window, slightly right.
• In the same area select "Left Click Green Window Button" from the Triggers menu.
• Also in the same area; select "Maximize" from the Predefined Actions menu.

Chrome

• Click the "+" symbol.
• Locate and select Chrome.
• Follow the instructions above.