[FIX] mail: incoming email parsing
[FIX] mail: incoming email parsing

Correctly flag and remove nodes to remove containing odoo buttons.

Backport of revision aece706603987b99008fd8e6fdfa0bd47f0e0bb8 of saas7.

ygol/odoo,microcom/odoo,dfang/odoo,storm-computers/odoo,microcom/odoo,dfang/odoo,laslabs/odoo,ygol/odoo,Elico-Corp/odoo_OCB,stephen144/odoo,laslabs/odoo,dfang/odoo,laslabs/odoo,dfang/odoo,ygol/odoo,hip-odoo/odoo,hip-odoo/odoo,storm-computers/odoo,hip-odoo/odoo,stephen144/odoo,laslabs/odoo,Elico-Corp/odoo_OCB,ygol/odoo,storm-computers/odoo,Elico-Corp/odoo_OCB,storm-computers/odoo,Elico-Corp/odoo_OCB,bplancher/odoo,optima-ict/odoo,microcom/odoo,sysadminmatmoz/OCB,ygol/odoo,dfang/odoo,laslabs/odoo,bplancher/odoo,storm-computers/odoo,sysadminmatmoz/OCB,laslabs/odoo,hip-odoo/odoo,stephen144/odoo,optima-ict/odoo,stephen144/odoo,microcom/odoo,Elico-Corp/odoo_OCB,storm-computers/odoo,optima-ict/odoo,dfang/odoo,bplancher/odoo,optima-ict/odoo,bplancher/odoo,sysadminmatmoz/OCB,sysadminmatmoz/OCB,microcom/odoo,microcom/odoo,Elico-Corp/odoo_OCB,optima-ict/odoo,stephen144/odoo,sysadminmatmoz/OCB,bplancher/odoo,hip-odoo/odoo,sysadminmatmoz/OCB,optima-ict/odoo,bplancher/odoo,stephen144/odoo,hip-odoo/odoo,ygol/odoo,ygol/odoo,sysadminmatmoz/OCB