Allow application to control computer (assistive devices) on Mavericks via Terminal?
The settings are stored in /Library/Application Support/com.apple.TCC/TCC.db:

$ sudo sqlite3 /Library/Application\ Support/com.apple.TCC/TCC.db 'select * from access'
kTCCServiceAccessibility|com.apple.ScriptEditor2|0|1|0|��

kTCCServiceAccessibility|com.red-sweater.FastScripts|0|1|0|��

kTCCServiceAccessibility|com.apple.AccessibilityInspector|0|1|0|��

kTCCServiceAccessibility|com.slate.Slate|0|1|0|��

kTCCServiceAccessibility|com.apple.Automator|0|1|1|
kTCCServiceAccessibility|com.googlecode.iterm2|0|1|1|


The schema, as given by sudo sqlite3 /Library/Application\ Support/com.apple.TCC/TCC.db '.schema access', is:

CREATE TABLE access (service TEXT NOT NULL, client TEXT NOT NULL, client_type INTEGER NOT NULL, allowed INTEGER NOT NULL, prompt_count INTEGER NOT NULL, csreq BLOB, CONSTRAINT key PRIMARY KEY (service, client, client_type));


On my installation the last four columns (client_type, allowed, prompt_count, and csreq) are 0|1|0|\xfa\xde\x0c for applications that were added after the "example.app" would like to control this computer using accessibility features dialog was shown and 0|1|1| for applications that I added by dropping them to the list in System Preferences.

~/Library/Preferences/com.apple.universalaccessAuthWarning.plist contains a list of applications for which the warning dialog has been shown:

$ defaults read com.apple.universalaccessAuthWarning
{
    "/Applications/Automator.app" = 1;
    "/Applications/Automator.app/Contents/MacOS/Automator" = 1;
    "/Applications/FastScripts.app" = 1;
    "/Applications/FastScripts.app/Contents/MacOS/FastScripts" = 1;
    "/Applications/Slate.app" = 1;
    "/Applications/Slate.app/Contents/MacOS/Slate" = 1;
    "/Applications/Utilities/AppleScript Editor.app" = 1;
    "/Applications/Utilities/AppleScript Editor.app/Contents/MacOS/AppleScript Editor" = 1;
    "/Applications/Xcode.app/Contents/Applications/Accessibility Inspector.app" = 1;
    "/Applications/Xcode.app/Contents/Applications/Accessibility Inspector.app/Contents/MacOS/Accessibility Inspector" = 1;
    "/Applications/iTerm.app" = 1;
    "/Applications/iTerm.app/Contents/MacOS/iTerm" = 1;
    "/Users/lauri/Desktop/aa.app" = 1;
    "/Users/lauri/Desktop/aa.app/Contents/MacOS/applet" = 1;
    "com.apple.AccessibilityInspector" = 1;
    "com.apple.Automator" = 1;
    "com.apple.ScriptEditor.id.aa" = 1;
    "com.apple.ScriptEditor2" = 1;
    "com.red-sweater.FastScripts" = 1;
    "com.slate.Slate" = 1;
}    


I couldn't figure out how to actually allow access for assistive devices for an application though. I tried for example running these commands:

sudo sqlite3 /Library/Application\ Support/com.apple.TCC/TCC.db 'insert into access values ("kTCCServiceAccessibility","com.apple.ScriptEditor.id.qq",0,1,0,"'$'\xfa\xde\x0c''");'
defaults write com.apple.universalaccessAuthWarning com.apple.ScriptEditor.id.qq -bool true
defaults write com.apple.universalaccessAuthWarning /Users/lauri/Desktop/qq.app -bool true
defaults write com.apple.universalaccessAuthWarning /Users/lauri/Desktop/qq.app/Contents/MacOS/applet -bool true
sudo killall tccd


I also tried restarting to apply the changes and setting the last four columns to 0,1,1,"".