originalLine='<com.whatsapp.voipcalling.VideoCallParticipantViewLayout android:id="@id/video_participant_views" android:layout_width="fill_parent" android:layout_height="fill_parent"/>'

escParamToChange="android:layout_width"
value="10dip"

replacementLine=$(echo ${originalLine} | sed -E 's/'${escParamToChange}'=[^ ]*/'${escParamToChange}'="'${value}'"/')

echo ${replacementLine}

<com.whatsapp.voipcalling.VideoCallParticipantViewLayout android:id="@id/video_participant_views" android:layout_width="10dip" android:layout_height="fill_parent"/>

<com.whatsapp.voipcalling.VideoCallParticipantViewLayout android:id="@id/video_participant_views" android:layout_width="fill_parent" android:layout_height="10dip"