Monitor lacks provision to read memory stat at the moment of query

[varumugam123]

Right now, Monitor plugin is implemented to read memory information from plugins at periodic intervals. But sometimes returning cached value are not desirable. If any component is interested in memory consumption of a plugin (say WebKitBrowser) at the moment, the only option we have is to increase the frequency of memory read.

Having a provision to force read memory stat from plugins would be of help in such scenarios.